Transmission apparatus of agricultural working automobile

ABSTRACT

The present invention relates to a transmission apparatus of an agricultural working automobile, the transmission apparatus comprising: a first gear-shifting part for performing gear-shifting to adjust the speed of an agricultural working automobile; and a second gear-shifting part for performing gear-shifting to adjust the speed of the agricultural working automobile, wherein the second gear-shifting part comprises a sub-gear-shifting drive mechanism for performing gear-shifting, using one operation selected from among an operation transferred through a first power transmission path from the first gear-shifting part and an operation transferred through a second power transmission path from the first gear-shifting part.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a National Stage of International ApplicationNo. PCT/KR2017/003554 filed Mar. 31, 2017, which claims priority toKorean Application No. 10-2016-0040468, filed Apr. 1, 2016, KoreanApplication No. 10-2016-0041428, filed on Apr. 5, 2016, KoreanApplication No. 10-2017-0041655, filed on Mar. 31, 2017, and KoreanApplication No. 10-2017-0041665 filed on Mar. 31, 2017 the disclosuresof which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a transmission apparatus of anagricultural working automobile configured to adjust a speed of theagricultural working automobile.

BACKGROUND ART

Agricultural working automobiles are used to cultivate crops, which arenecessary for human life, using soil. For example, combines, tractors,or the like correspond to the agricultural working automobile. Thecombine performs the work of reaping and threshing crops such as rice,barley, wheat, beans, or the like. The tractor performs the worknecessary for cultivating crops using a traction force.

The agricultural working automobile includes a transmission apparatus toadjust a torque, a speed, etc. as needed during work.

FIG. 1 is a schematic block diagram of a transmission apparatus of anagricultural working automobile according to the related art.

Referring to FIG. 1, a transmission apparatus 11 of an agriculturalworking automobile according to the related art includes a firstgear-shifting part 12 for gear shifting and a second gear-shifting part13 for gear shifting.

The first gear-shifting part 12 includes a first drive mechanism 121driven by a driving power provided from an engine and an outputmechanism 122 driven by a driving power provided from the first drivemechanism 121. The first drive mechanism 121 performs the gear shiftingusing a plurality of gears and a sleeve.

The second gear-shifting part 13 includes an input mechanism 131 drivenby a driving power provided from the output mechanism 122 and a seconddrive mechanism 133 driven by a driving power provided from the inputmechanism 131. The second drive mechanism 133 performs the gear shiftingusing a plurality of gears and a sleeve.

In the transmission apparatus 11 of an agricultural working automobileaccording to the related art, the second gear-shifting part 13 and thefirst gear-shifting part 12 are connected to each other only through aconnection between the output mechanism 122 and the input mechanism 131.

That is, in the transmission apparatus 11 of an agricultural workingautomobile according to the related art, the second gear-shifting part13 and the first gear-shifting part 12 are connected to each other onlythrough one power transmission path.

Accordingly, in the transmission apparatus 11 of an agricultural workingautomobile according to the related art, since a driving power providedthrough one power transmission path needs to be transmitted to each ofthe gears of the second drive mechanism 133 by the input mechanism 131,a configuration of the input mechanism 131 is complicated, therebyincreasing a difficulty in manufacturing work.

DISCLOSURE Technical Problem

Therefore, the present invention is designed to solve the problems andis for providing a transmission apparatus of an agricultural workingautomobile which alleviates complexity of a configuration and reducesdifficulty of manufacturing work.

Technical Solution

To solve the above problems, the present invention may include thefollowing configurations.

A transmission apparatus of an agricultural working automobile accordingto the present invention includes a first gear-shifting part whichperforms gear shifting to adjust a speed of an agricultural workingautomobile, and a second gear-shifting part which performs gear shiftingto adjust the speed of the agricultural working automobile. The secondgear-shifting part includes a sub gear-shifting part which performs gearshifting for a driving power transmitted from the first gear-shiftingpart, the sub gear-shifting part includes a sub gear-shifting drivemechanism which performs gear shifting using a driving power transmittedthrough one power transmission path selected from a first powertransmission path through which the driving power, in which the gearshifting is performed, is transmitted from the first gear-shifting part,and a second power transmission path through which the driving power, inwhich the gear shifting is performed, is transmitted from the firstgear-shifting part.

Advantageous Effects

The present invention can provide the following effects.

The present invention is implemented so that a first gear-shifting partand a second gear-shifting part are connected to each other through aplurality power transmission paths, thereby alleviating complexity of aconfiguration thereof and improving ease of manufacturing work.

DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic block diagram of a transmission apparatus of anagricultural working automobile according to the related art.

FIG. 2 is a schematic block diagram of a transmission apparatus of anagricultural working automobile according to the present invention.

FIG. 3 is a schematic block diagram of a transmission apparatus of anagricultural working automobile according to a first embodiment of thepresent invention.

FIG. 4 is a schematic power transmission diagram of the transmissionapparatus of an agricultural working automobile according to the firstembodiment of the present invention.

FIG. 5 is a schematic power transmission diagram for describing adisadvantage of a case in which a main gear-shifting part is connectedto a sub gear-shifting part through one power transmission path.

FIGS. 6 to 13 are schematic power transmission diagrams illustratingflows of power transmission according to gear-shifting stages in thetransmission apparatus of an agricultural working automobile accordingto the first embodiment of the present invention.

FIGS. 14 to 16 are schematic power transmission diagrams for describinga modified embodiment of the sub gear-shifting part in the transmissionapparatus of an agricultural working automobile according to the firstembodiment of the present invention.

FIGS. 17 and 18 are schematic power transmission diagrams for describinga modified embodiment of a main gear-shifting output member in thetransmission apparatus of an agricultural working automobile accordingto the first embodiment of the present invention.

FIG. 19 is a schematic block diagram of a transmission apparatus of anagricultural working automobile according to a modified first embodimentof the present invention.

FIGS. 20 to 22 are schematic power transmission diagrams of thetransmission apparatus of an agricultural working automobile accordingto the modified first embodiment of the present invention.

FIGS. 23 and 24 are schematic block diagrams of a transmission apparatusof an agricultural working automobile according to a second embodimentof the present invention.

FIGS. 25 to 27 are schematic power transmission diagrams of thetransmission apparatus of an agricultural working automobile accordingto the second embodiment of the present invention.

FIGS. 28 to 30 are schematic power transmission diagrams for describinga modified embodiment of a sub gear-shifting part in the transmissionapparatus of an agricultural working automobile according to the secondembodiment of the present invention.

FIGS. 31 and 32 are schematic power transmission diagrams for describinga modified embodiment of a main gear-shifting output member and a subgear-shifting input member in the transmission apparatus of anagricultural working automobile according to the second embodiment ofthe present invention.

FIG. 33 is a schematic power transmission diagram for describing amodified embodiment of an ultra-low speed gear-shifting part in thetransmission apparatus of an agricultural working automobile accordingto the second embodiment of the present invention.

FIG. 34 is a schematic power transmission diagram for describing anothermodified embodiment of the ultra-low speed gear-shifting part in thetransmission apparatus of an agricultural working automobile accordingto the second embodiment of the present invention.

FIG. 35 is a schematic block diagram of a transmission apparatus of anagricultural working automobile according to a modified secondembodiment of the present invention.

FIGS. 36 to 40 are schematic power transmission diagrams of thetransmission apparatus of an agricultural working automobile accordingto the modified second embodiment of the present invention.

BEST MODE

Hereinafter, embodiments of a transmission apparatus of an agriculturalworking automobile according to the present invention will be describedin detail with reference to the accompanying drawings.

Referring to FIGS. 2 and 3, a transmission apparatus 1 of anagricultural working automobile according to the present invention isinstalled in an agricultural working automobile (not shown) such astractors, combines or the like. The transmission apparatus 1 of anagricultural working automobile according to the present inventionperforms a gear-shifting function, which adjusts a torque, a speed, orthe like as needed, in the agricultural working automobile.

The transmission apparatus 1 of an agricultural working automobileaccording to the present invention may include a first gear-shiftingpart 110 which performs gear shifting to adjust the speed of theagricultural working automobile, and a second gear-shifting part 120which performs gear shifting to adjust the speed of the agriculturalworking automobile. The second gear-shifting part 120 may include a subgear-shifting part 3 (shown in FIG. 3) which performs the gear shiftingon the driving power transmitted from the first gear-shifting part 110.The sub gear-shifting part 3 may include a sub gear-shifting drivemechanism 33 which performs the gear shifting using the driving powertransmitted through one power transmission path selected from a firstpower transmission path TP1 through which the driving power, in whichthe gear shifting is performed, is transmitted from the firstgear-shifting part 110, and a second power transmission path TP2 throughwhich the driving power, in which the gear shifting is performed, istransmitted from the first gear-shifting part 110.

Accordingly, the transmission apparatus 1 of an agricultural workingautomobile according to the present invention is implemented such thatthe first gear-shifting part 110 and the second gear-shifting part 120are connected to each other through the plurality of power transmissionpaths TP1 and TP2. Thus, the transmission apparatus 1 of an agriculturalworking automobile according to the present invention may divide aconfiguration for transmitting the driving power to the subgear-shifting drive mechanism 33 into each of the first powertransmission path TP1 and the second power transmission path TP2.Accordingly, the transmission apparatus 1 of an agricultural workingautomobile according to the present invention may alleviate complexityof the configuration for transmitting the driving power in which thegear shifting is performed at different speeds to the sub gear-shiftingdrive mechanism 33 and also improve ease of manufacturing work.

Here, the transmission apparatus 1 of an agricultural working automobileaccording to the present invention may mainly include a first embodimentand a second embodiment according to a structure of the firstgear-shifting part 110. Hereinafter, the transmission apparatus 1 of anagricultural working automobile according to the first and secondembodiments of the present invention will be sequentially described withreference to the accompanying drawings.

First Embodiment

A transmission apparatus 1 of an agricultural working automobileaccording to a first embodiment of the present invention may include thefirst gear-shifting part 110 and the second gear-shifting part 120.

Referring to FIG. 2, the first gear-shifting part 110 performs gearshifting to adjust a speed of the agricultural working automobile. Thefirst gear-shifting part 110 may be installed in the agriculturalworking automobile. The first gear-shifting part 110 may be connected tothe second gear-shifting part 120. The first gear-shifting part 110 mayperform the gear shifting on the driving power provided from a firstexternal device and output the driving power in which the gear shiftingis performed to the second gear-shifting part 120. The secondgear-shifting part 120 may perform additional gear shifting on thedriving power transmitted from the first gear-shifting part 110 andoutput the driving power in which the additional gear shifting isperformed to a second external device. The first external device may bean engine (not shown) of the agricultural working automobile. The secondexternal device may be a driving device (not shown) of the agriculturalworking automobile.

Referring to FIGS. 2 and 3, the first gear-shifting part 110 may includea main gear-shifting part 2.

The main gear-shifting part 2 performs first gear shifting to adjust thespeed of the agricultural working automobile. The main gear-shiftingpart 2 may perform the first gear shifting on the driving power providedfrom the first external device, and output the driving power in whichthe first gear shifting is performed. The main gear-shifting part 2 mayoutput the driving power in which the first gear shifting is performedto the second gear-shifting part 120. When the main gear-shifting part 2is implemented to be directly connected to the sub gear-shifting part 3,the main gear-shifting part 2 may output the driving power in which thefirst gear shifting is performed to the sub gear-shifting part 3.

Referring to FIGS. 3 and 4, the main gear-shifting part 2 may include amain gear-shifting drive mechanism 21 and a main gear-shifting outputmechanism 22.

The main gear-shifting drive mechanism 21 performs the first gearshifting on the driving power provided from the engine (not shown). Themain gear-shifting drive mechanism 21 may be connected to a maingear-shifting input mechanism 20. The main gear-shifting input mechanism20 is rotated by the driving power provided from the engine. The maingear-shifting input mechanism 20 may function as a rotation shaft in themain gear-shifting drive mechanism 21. For example, the maingear-shifting input mechanism 20 may be a shaft. The main gear-shiftingdrive mechanism 21 may perform the first gear shifting on the drivingpower transmitted through the main gear-shifting input mechanism 20. Themain gear-shifting drive mechanism 21 may be connected to the maingear-shifting output mechanism 22. The main gear-shifting drivemechanism 21 may perform the first gear shifting in conjunction with themain gear-shifting output mechanism 22.

The main gear-shifting drive mechanism 21 may include a plurality ofmain gear-shifting drive gears 211. The main gear-shifting drivemechanism 21 may include a number of main gear-shifting drive gears 211corresponding to a first gear-shifting stage performable by the maingear-shifting part 2. Each of the main gear-shifting drive gears 211transmits the driving power using a plurality of gear teeth and may be,for example, a helical gear.

The main gear-shifting drive mechanism 21 may include at least one maingear-shifting sleeve 212. The main gear-shifting sleeve 212 may beselectively connected to any one of the two main gear-shifting drivegears 211. The main gear-shifting sleeve 212 may be connected to acorresponding main gear-shifting drive gear 211 by being selectivelyengaged with any one of the two main gear-shifting drive gears 211. Themain gear-shifting sleeve 212 may be selectively connected to any one ofthe two main gear-shifting drive gears 211 by a gear-shifting operationof an operator. The main gear-shifting sleeve 212 may be coupled to themain gear-shifting input mechanism 20. Accordingly, the maingear-shifting sleeve 212 may rotate as the main gear-shifting inputmechanism 20 rotates. The main gear-shifting sleeve 212 may rotate aboutthe main gear-shifting input mechanism 20 as a rotation shaft. In thiscase, the main gear-shifting drive gears 211 connected to the maingear-shifting sleeve 212 may rotate. The main gear-shifting sleeve 212may be a synchronizer sleeve. The main gear-shifting drive mechanism 21may include a required number of the main gear-shifting sleeves 212according to the first gear-shifting stage to be performed by the maingear-shifting part 2.

For example, the main gear-shifting drive mechanism 21 may include afirst main gear-shifting drive gear 211 a, a second main gear-shiftingdrive gear 211 b, and a first main gear-shifting sleeve 212 a. In thiscase, the main gear-shifting drive mechanism 21 may be implemented asdescribed below.

The first main gear-shifting drive gear 211 a may be idly coupled to themain gear-shifting input mechanism 20. A bearing (not shown) may beinstalled between the first main gear-shifting drive gear 211 a and themain gear-shifting input mechanism 20. The first main gear-shiftingdrive gear 211 a may include a first drive input gear 2111 a for beingconnected to the first main gear-shifting sleeve 212 a and a first driveoutput gear 2112 a for being connected to the main gear-shifting outputmechanism 22.

The second main gear-shifting drive gear 211 b may be idly coupled tothe main gear-shifting input mechanism 20. A bearing (not shown) may beinstalled between the second main gear-shifting drive gear 211 b and themain gear-shifting input mechanism 20. The second main gear-shiftingdrive gear 211 b and the first main gear-shifting drive gear 211 a maybe disposed to be spaced apart from each other in a first axis direction(an X axis direction). The first axis direction (the X axis direction)is a direction parallel to the main gear-shifting input mechanism 20.The second main gear-shifting drive gear 211 b may include a seconddrive input gear 2111 b for being connected to the first maingear-shifting sleeve 212 a and a second drive output gear 2112 b forbeing connected to the main gear-shifting output mechanism 22. When thesecond main gear-shifting drive gear 211 b performs the gear shifting ata higher speed than the first main gear-shifting drive gear 211 a, thesecond main gear-shifting drive gear 2112 b may be implemented to have agreater diameter than the first drive output gear 2112 a.

The first main gear-shifting sleeve 212 a may be coupled to the maingear-shifting input mechanism 20 so as to be positioned between thefirst main gear-shifting drive gear 211 a and the second maingear-shifting drive gear 211 b. The first main gear-shifting sleeve 212a may be coupled to the main gear-shifting input mechanism 20 to bemovable in the first axis direction (the X axis direction). Accordingly,the first main gear-shifting sleeve 212 a may be selectively connectedto the first main gear-shifting drive gear 211 a or the second maingear-shifting drive gear 211 b to perform the first gear shifting. Inthis case, the first main gear-shifting sleeve 212 a may move along thefirst axis direction (the X axis direction) by the gear-shiftingoperation of the operator. When the first main gear-shifting sleeve 212a moves to a left side with reference to FIG. 4, the first maingear-shifting sleeve 212 a may be engaged with the first maingear-shifting drive gear 211 a to rotate the first main gear-shiftingdrive gear 211 a. Accordingly, the main gear-shifting part 2 may performthe first gear shifting using the first main gear-shifting drive gear211 a. When the first main gear-shifting sleeve 212 a moves to a rightside with reference to FIG. 4, the first main gear-shifting sleeve 212 amay be engaged with the second main gear-shifting drive gear 211 b torotate the second main gear-shifting drive gear 211 b. Accordingly, themain gear-shifting part 2 may perform the first gear shifting using thesecond main gear-shifting drive gear 211 b.

As described above, when the main gear-shifting drive mechanism 21includes the first main gear-shifting sleeve 212 a, the second maingear-shifting drive gear 211 b, and the first main gear-shifting drivegear 211 a, the main gear-shifting part 2 may perform the first gearshifting in two stages.

For example, the main gear-shifting drive mechanism 21 may furtherinclude a third main gear-shifting drive gear 211 c, a fourth maingear-shifting drive gear 211 d, and a second main gear-shifting sleeve212 b in addition to the first main gear-shifting drive gear 211 a, thesecond main gear-shifting drive gear 211 b, and the first maingear-shifting sleeve 212 a. In this case, the main gear-shifting drivemechanism 21 may be implemented as described below.

The third main gear-shifting drive gear 211 c may be idly coupled to themain gear-shifting input mechanism 20. A bearing (not shown) may beinstalled between the third main gear-shifting drive gear 211 c and themain gear-shifting input mechanism 20. The third main gear-shiftingdrive gear 211 c may include a third drive input gear 2111 c for beingconnected to the second main gear-shifting sleeve 212 b and a thirddrive output gear 2112 c for being connected to the main gear-shiftingoutput mechanism 22.

The fourth main gear-shifting drive gear 211 d may be idly coupled tothe main gear-shifting input mechanism 20. A bearing (not shown) may beinstalled between the fourth main gear-shifting drive gear 211 d and themain gear-shifting input mechanism 20. The fourth main gear-shiftingdrive gear 211 d and the third main gear-shifting drive gear 211 c maybe disposed to be spaced apart from each other in the first axisdirection (the X axis direction). The fourth main gear-shifting drivegear 211 d may be disposed to be positioned between the third maingear-shifting drive gear 211 c and the first main gear-shifting drivegear 211 a. The fourth main gear-shifting drive gear 211 d may include afourth drive input gear 2111 d for being connected to the second maingear-shifting sleeve 212 b and a fourth drive output gear 2112 d forbeing connected to the main gear-shifting output mechanism 22. When thefourth main gear-shifting drive gear 211 d performs the gear shifting ata higher speed than the third main gear-shifting drive gear 211 c, thefourth drive output gear 2112 d may be implemented to have a greaterdiameter than the third drive output gear 2112 c. When the fourth maingear-shifting drive gear 211 d is implemented as a fourth speed stage,the third main gear-shifting drive gear 211 c is implemented as a thirdspeed stage, the second main gear-shifting drive gear 211 b isimplemented as a second speed stage, and the first main gear-shiftingdrive gear 211 a is implemented as a first speed stage, in order fromthe highest speed to the lowest speed, the fourth drive output gear 2112d may be implemented to have the greatest diameter and the first driveoutput gear 2112 a may be implemented to have the smallest diameter. Thesecond drive output gear 2112 b may be implemented to have a greaterdiameter than the first drive output gear 2112 a and a smaller diameterthan the third drive output gear 2112 c.

The second main gear-shifting sleeve 212 b may be coupled to the maingear-shifting input mechanism 20 so as to be positioned between thethird main gear-shifting drive gear 211 c and the fourth maingear-shifting drive gear 211 d. The second main gear-shifting sleeve 212b may be coupled to the main gear-shifting input mechanism 20 to bemovable in the first axis direction (the X axis direction). Accordingly,the second main gear-shifting sleeve 212 b may be selectively connectedto the third main gear-shifting drive gear 211 c or the fourth maingear-shifting drive gear 211 d to perform the first gear shifting. Inthis case, the second main gear-shifting sleeve 212 b may move along thefirst axis direction (the X axis direction) by the gear-shiftingoperation of the operator. When the second main gear-shifting sleeve 212b moves to the left side with reference to FIG. 4, the second maingear-shifting sleeve 212 b may be engaged with the third maingear-shifting drive gear 211 c to rotate the third main gear-shiftingdrive gear 211 c. Accordingly, the main gear-shifting part 2 may performthe first gear shifting using the third main gear-shifting drive gear211 c. When the second main gear-shifting sleeve 212 b moves to theright side with reference to FIG. 4, the second main gear-shiftingsleeve 212 b may be engaged with the fourth main gear-shifting drivegear 211 d to rotate the fourth main gear-shifting drive gear 211 d.Accordingly, the main gear-shifting part 2 may perform the first gearshifting using the fourth main gear-shifting drive gear 211 d.

The second main gear-shifting sleeve 212 b, the fourth maingear-shifting drive gear 211 d, and the third main gear-shifting drivegear 211 c may be disposed on positions spaced apart from the first maingear-shifting sleeve 212 a, the second main gear-shifting drive gear 211b, and the first main gear-shifting drive gear 211 a in the first axisdirection (the X axis direction). In this case, the main gear-shiftinginput mechanism 20 may be installed to be positioned in each of thefourth main gear-shifting drive gear 211 d, the third main gear-shiftingdrive gear 211 c, the second main gear-shifting drive gear 211 b, andthe first main gear-shifting drive gear 211 a.

As described above, when the main gear-shifting drive mechanism 21includes the second main gear-shifting sleeve 212 b, the fourth maingear-shifting drive gear 211 d, the third main gear-shifting drive gear211 c, the first main gear-shifting sleeve 212 a, the second maingear-shifting drive gear 211 b, and the first main gear-shifting drivegear 211 a, the main gear-shifting part 2 may perform the first gearshifting in four stages.

Although not shown in the drawings, the main gear-shifting part 2 may beimplemented to perform the first gear shifting in six stages, eightstages, or the like. When the first gear shifting is performed in thesix stages, the main gear-shifting part 2 may include six maingear-shifting drive gears 211 having different diameters and three maingear-shifting sleeves 212. When the first gear shifting is performed inthe eight stages, the main gear-shifting part 2 may include eight maingear-shifting drive gears 211 having different diameters and four maingear-shifting sleeves 212.

Meanwhile, the main gear-shifting part 2 may be implemented to performthe first gear shifting in three stages, five stages, seven stages, orthe like. When the first gear shifting is performed in the three stages,the main gear-shifting part 2 may include three main gear-shifting drivegears 211 having different diameters and two main gear-shifting sleeves212. In this case, one main gear-shifting sleeve 212 among the two maingear-shifting sleeves 212 may only move to one side to be connected toone main gear-shifting drive gear 211. When the first gear shifting isperformed in the five stages, the main gear-shifting part 2 may includefive main gear-shifting drive gears 211 having different diameters andthree main gear-shifting sleeves 212. In this case, one maingear-shifting sleeve 212 among the three main gear-shifting sleeves 212may only move to one side to be connected to one main gear-shiftingdrive gear 211. When the first gear shifting is performed in the sevenstages, the main gear-shifting part 2 may include seven maingear-shifting drive gears 211 having different diameters and four maingear-shifting sleeves 212. In this case, one main gear-shifting sleeve212 among the four main gear-shifting sleeves 212 may only move to oneside to be connected to one main gear-shifting drive gear 211.

Referring to FIGS. 2 to 4, the main gear-shifting output mechanism 22 isdriven according to the driving power of the main gear-shifting drivemechanism 21. The main gear-shifting output mechanism 22 is driven inconjunction with the main gear-shifting drive mechanism 21 to output thedriving power in which the first gear shifting is performed to thesecond gear-shifting part 120. When the main gear-shifting part 2 isimplemented to be directly connected to the sub gear-shifting part 3,the main gear-shifting output mechanism 22 may output the driving powerin which the first gear shifting is performed to the sub gear-shiftingpart 3.

The main gear-shifting output mechanism 22 may include a maingear-shifting output member 221.

The main gear-shifting output member 221 is connected to the secondgear-shifting part 120. Accordingly, the main gear-shifting outputmember 221 may output the driving power in which the first gear shiftingis performed to the second gear-shifting part 120. The maingear-shifting output member 221 may be disposed parallel to the maingear-shifting input mechanism 20. The main gear-shifting output member221 may function as a rotation shaft in the main gear-shifting outputmechanism 22. For example, the main gear-shifting output member 221 maybe a shaft. When the main gear-shifting part 2 is implemented to bedirectly connected to the sub gear-shifting part 3, the maingear-shifting output member 221 may be connected to the subgear-shifting part 3 to output the driving power in which the first gearshifting is performed to the sub gear-shifting part 3.

The main gear-shifting output mechanism 22 may include a plurality ofmain gear-shifting output gears 222.

The main gear-shifting output gears 222 are connected to the maingear-shifting output member 221. The main gear-shifting output gears 222may be connected to the main gear-shifting output member 221 by beingcoupled to the main gear-shifting output member 221. The maingear-shifting output gears 222 may rotate about the main gear-shiftingoutput member 221 as a rotation shaft. Each of the main gear-shiftingoutput gears 222 may be connected to each of the main gear-shiftingdrive gears 211 of the main gear-shifting drive mechanism 21.Accordingly, the main gear-shifting output gears 222 may rotate the maingear-shifting output member 221 by rotating by the driving powerprovided from the main gear-shifting drive gears 221. Each of the maingear-shifting output gears 222 may be connected to each of the maingear-shifting drive gears 211 by being engaged with each of the maingear-shifting drive gears 211. Each of the main gear-shifting outputgears 222 may receive the driving power using a plurality of gear teeth.For example, the main gear-shifting output gears 222 may be helicalgears.

The main gear-shifting output mechanism 22 may include the same numberof main gear-shifting output gears 222 as the main gear-shifting drivegears 211 of the main gear-shifting drive mechanism 21. For example,when the main gear-shifting drive mechanism 21 includes the first maingear-shifting drive gear 211 a, the second main gear-shifting drive gear211 b, and the first main gear-shifting sleeve 212 a, the maingear-shifting output mechanism 22 may include a first main gear-shiftingoutput gear 222 a connected to the first main gear-shifting drive gear211 a and a second main gear-shifting output gear 222 b connected to thesecond main gear-shifting drive gear 211 b.

The first main gear-shifting output gear 222 a may be coupled to themain gear-shifting output member 221. The first main gear-shiftingoutput gear 222 a may be connected to the first main gear-shifting drivegear 211 a by being engaged with the first drive output gear 2112 a ofthe first main gear-shifting drive gear 211 a. When the first maingear-shifting sleeve 212 a is connected to the first main gear-shiftingdrive gear 211 a, the first main gear-shifting output gear 222 a mayrotate the main gear-shifting output member 221 while rotating as thefirst main gear-shifting drive gear 211 a rotates. When the first maingear-shifting sleeve 212 a is connected to the second main gear-shiftingdrive gear 211 b, the first main gear-shifting output gear 222 a mayrotate as the main gear-shifting output member 221 rotates. In thiscase, the main gear-shifting output member 221 may rotate as the secondmain gear-shifting output gear 222 b rotates. The first maingear-shifting output gear 222 a may be implemented to have a smallerdiameter than the first main gear-shifting drive gear 211 a.Accordingly, the first main gear-shifting output gear 222 a rotates themain gear-shifting output member 221 while rotating, thereby achievingacceleration gear shifting in which the speed is increased. The firstmain gear-shifting output gear 222 a may also be implemented to have agreater diameter than the first main gear-shifting drive gear 211 a. Inthis case, the first main gear-shifting output gear 222 a rotates themain gear-shifting output member 221 while rotating, thereby achievingdeceleration gear shifting in which the speed becomes slow. The firstmain gear-shifting output gear 222 a may also be implemented to have thesame diameter as the first main gear-shifting drive gear 211 a. In thiscase, the driving power may be transmitted from the first maingear-shifting drive gear 211 a to the first main gear-shifting outputgear 222 a without changing the speed.

The second main gear-shifting output gear 222 b may be coupled to themain gear-shifting output member 221. The second main gear-shiftingoutput gear 222 b may be coupled to the main gear-shifting output member221 at a position spaced apart from the first main gear-shifting outputgear 222 a in the first axis direction (the X axis direction). Thesecond main gear-shifting output gear 222 b may be connected to thesecond main gear-shifting drive gear 211 b by being engaged with thesecond main gear-shifting drive gear 2112 b of the second maingear-shifting drive gear 211 b. When the first main gear-shifting sleeve212 a is connected to the second main gear-shifting drive gear 211 b,the second main gear-shifting output gear 222 b may rotate the maingear-shifting output member 221 while rotating as the second maingear-shifting drive gear 211 b rotates. When the first maingear-shifting sleeve 212 a is connected to the first main gear-shiftingdrive gear 211 a, the second main gear-shifting output gear 222 b mayrotate as the main gear-shifting output member 221 rotates. In thiscase, the main gear-shifting output member 221 may rotate as the firstmain gear-shifting output gear 222 a rotates. The second maingear-shifting output gear 222 b may be implemented to have a smallerdiameter than the second main gear-shifting drive gear 211 b so that theacceleration gear shifting is achieved. The second main gear-shiftingoutput gear 222 b may also be implemented to have a greater diameterthan the second main gear-shifting drive gear 211 b so that thedeceleration gear-shifting is achieved. The second main gear-shiftingoutput gear 222 b may also be implemented to have the same diameter asthe second main gear-shifting drive gear 211 b so that there is no speedchange. The second main gear-shifting output gear 222 b may beimplemented to have a smaller diameter than the first main gear-shiftingoutput gear 222 a. In this case, the second main gear-shifting drivegear 211 b may be implemented to perform the gear shifting at a higherspeed than the first main gear-shifting drive gear 211 a.

For example, when the main gear-shifting drive mechanism 21 includes thefirst main gear-shifting drive gear 211 a, the second main gear-shiftingdrive gear 211 b, the first main gear-shifting sleeve 212 a, the thirdmain gear-shifting drive gear 211 c, the fourth main gear-shifting drivegear 211 d, and the second main gear-shifting sleeve 212 b, the maingear-shifting output mechanism 22 may include a third main gear-shiftingoutput gear 222 c connected to the third main gear-shifting drive gear211 c and a fourth main gear-shifting output gear 222 d connected to thefourth main gear-shifting drive gear 211 d in addition to the first maingear-shifting output gear 222 a and the second main gear-shifting outputgear 222 b.

The third main gear-shifting output gear 222 c may be coupled to themain gear-shifting output member 221. The third main gear-shiftingoutput gear 222 c may be connected to the third main gear-shifting drivegear 211 c by being engaged with the third drive output gear 2112 c ofthe third main gear-shifting drive gear 211 c. When the second maingear-shifting sleeve 212 b is connected to the third main gear-shiftingdrive gear 211 c, the third main gear-shifting output gear 222 c mayrotate the main gear-shifting output member 221 while rotating as thethird main gear-shifting drive gear 211 c rotates. When the second maingear-shifting sleeve 212 b is not connected to the third maingear-shifting drive gear 211 c, the third main gear-shifting output gear222 c may rotate as the main gear-shifting output member 221 rotates. Inthis case, the main gear-shifting output member 221 may rotate as atleast one of the main gear-shifting output gears 222 a, 222 b, and 222 dother than the third main gear-shifting output gear 222 c rotates. Thethird main gear-shifting output gear 222 c may be implemented to have asmaller diameter than the third main gear-shifting drive gear 211 c sothat the acceleration gear shifting is achieved. The third maingear-shifting output gear 222 c may also be implemented to have agreater diameter than the third main gear-shifting drive gear 211 c sothat the deceleration gear shifting is achieved. The third maingear-shifting output gear 222 c may also be implemented to have the samediameter as the third main gear-shifting drive gear 211 c so that thereis no speed change. The third main gear-shifting output gear 222 c maybe implemented to have a smaller diameter than the second maingear-shifting output gear 222 b. In this case, the third maingear-shifting drive gear 211 c may be implemented to perform the gearshifting at a higher speed than the second main gear-shifting drive gear211 b.

The fourth main gear-shifting output gear 222 d may be coupled to themain gear-shifting output member 221. The fourth main gear-shiftingoutput gear 222 d may be coupled to the main gear-shifting output member221 at a position spaced apart from the third main gear-shifting outputgear 222 c in the first axis direction (the X axis direction). Thefourth main gear-shifting output gear 222 d may be disposed to bepositioned between the third main gear-shifting output gear 222 c andthe first main gear-shifting output gear 222 a. The fourth maingear-shifting output gear 222 d may be connected to the fourth maingear-shifting drive gear 211 d by being engaged with the fourth driveoutput gear 2112 d of the fourth main gear-shifting drive gear 211 d.When the second main gear-shifting sleeve 212 b is connected to thefourth main gear-shifting drive gear 211 d, the fourth maingear-shifting output gear 222 d may rotate the main gear-shifting outputmember 221 while rotating as the fourth main gear-shifting drive gear211 d rotates. When the second main gear-shifting sleeve 212 b is notconnected to the fourth main gear-shifting drive gear 211 d, the fourthmain gear-shifting output gear 222 d may rotate as the maingear-shifting output member 221 rotates. In this case, the maingear-shifting output member 221 may rotate as at least one of the maingear-shifting output gears 222 a, 222 b, and 222 c other than the fourthmain gear-shifting output gear 222 d rotates. The fourth maingear-shifting output gear 222 d may be implemented to have a smallerdiameter than the fourth main gear-shifting drive gear 211 d so that theacceleration gear shifting is achieved. The fourth main gear-shiftingoutput gear 222 d may also be implemented to have a greater diameterthan the fourth main gear-shifting drive gear 211 d so that thedeceleration gear shifting is achieved. The fourth main gear-shiftingoutput gear 222 d may also be implemented to have the same diameter asthe fourth main gear-shifting drive gear 211 d so that there is no speedchange. The fourth main gear-shifting output gear 222 d may beimplemented to have a smaller diameter than the third main gear-shiftingoutput gear 222 c. In this case, the fourth main gear-shifting drivegear 211 d may be implemented to perform the gear shifting at a higherspeed than the third main gear-shifting drive gear 211 c.

When fourth main gear-shifting drive gear 211 d is implemented as afourth speed stage, the third main gear-shifting drive gear 211 c isimplemented as a third speed stage, the second main gear-shifting drivegear 211 b is implemented as a second speed stage, and the first maingear-shifting drive gear 211 a is implemented as a first speed stage, inorder from the highest speed to the lowest speed, the fourth maingear-shifting output gear 222 d may be implemented to have the smallestdiameter, and the first main gear-shifting output gear 222 a may beimplemented to have the greatest diameter. The second main gear-shiftingoutput gear 222 b may be implemented to have a smaller diameter than thefirst main gear-shifting output gear 222 a and a greater diameter thanthe third main gear-shifting output gear 222 c.

As described above, when the main gear-shifting output mechanism 22includes the fourth main gear-shifting output gear 222 d, the third maingear-shifting output gear 222 c, the second main gear-shifting outputgear 222 b, and the first main gear-shifting output gear 222 a, the maingear-shifting part 2 may perform the first gear shifting in four stages.

Although not shown in the drawings, the main gear-shifting part 2 may beimplemented to perform the first gear shifting in even-numbered speedstages such as the six stages, the eight stages, or the like. The maingear-shifting part 2 may be implemented to perform the first gearshifting in odd-numbered speed stages such as the three stages, the fivestages, the seven stages, or the like.

Referring to FIG. 2, the second gear-shifting part 120 performsgear-shifting to adjust the speed of the agricultural workingautomobile. The second gear-shifting part 120 may be installed in theagricultural working automobile. The second gear-shifting part 120 maybe connected to the first gear-shifting part 110. The secondgear-shifting part 120 may perform additional gear shifting on thedriving power performed by the first gear-shifting part 110 and outputthe driving power to the second external device.

Referring to FIGS. 2 and 3, the second gear-shifting part 120 mayinclude the sub gear-shifting part 3.

The sub gear-shifting part 3 performs second gear shifting to adjust thespeed of the agricultural working automobile. The sub gear-shifting part3 may be connected to the first gear-shifting part 110. The subgear-shifting part 3 may be connected to the main gear-shifting part 2of the first gear-shifting part 110. In this case, the sub gear-shiftingpart 3 may perform the second gear shifting on the driving power inwhich the first gear shifting is performed and output the driving powerin which the second gear shifting is performed to the second externaldevice.

The sub gear-shifting part 3 may include the sub gear-shifting drivemechanism 33.

The sub gear-shifting drive mechanism 33 performs the gear shiftingusing the driving power transmitted through one power transmission pathselected between the first power transmission path TP1 and the secondpower transmission path TP2. The sub gear-shifting drive mechanism 33may be connected to the main gear-shifting part 2 through each of thefirst power transmission path TP1 and the second power transmission pathTP2. In this case, the main gear-shifting part 2 may output the drivingpower in which the first gear shifting is performed to the subgear-shifting part 3 through the first power transmission path TP1 andthe second power transmission path TP2. The sub gear-shifting drivemechanism 33 may perform the second gear shifting using the drivingpower transmitted through one power transmission path selected betweenthe first power transmission path TP1 and the second power transmissionpath TP2. Accordingly, the transmission apparatus 1 of an agriculturalworking automobile according to the first embodiment of the presentinvention may divide a configuration for transmitting the driving powerto the sub gear-shifting drive mechanism 33 into each of the first powertransmission path TP1 and the second power transmission path TP2,thereby alleviating complexity of the configuration for transmitting thedriving power in which the first gear shifting is performed to the subgear-shifting drive mechanism 33 and improving ease of manufacturingwork.

The sub gear-shifting drive mechanism 33 may be connected to a subgear-shifting output mechanism 30. The sub gear-shifting outputmechanism 30 may be rotated by the driving power in which the secondgear shifting is performed by the sub gear-shifting drive mechanism 33.The sub gear-shifting output mechanism 30 is connected to the secondexternal device. Accordingly, the sub gear-shifting part 3 may outputthe driving power, in which the second gear shifting is performed afterpassing through the first gear-shifting, to the second external devicethrough the sub gear-shifting output mechanism 30. The sub gear-shiftingoutput mechanism 30 may be a shaft.

Referring to FIGS. 3 and 4, the sub gear-shifting part 3 may include asub gear-shifting input mechanism 31 and a sub gear-shifting connectionmechanism 32.

The sub gear-shifting input mechanism 31 may be connected to the maingear-shifting part 2. Accordingly, the sub gear-shifting input mechanism31 may implement the first power transmission path through which thedriving power in which the first gear shifting is performed istransmitted from the main gear-shifting part 2. The sub gear-shiftinginput mechanism 31 may be connected to the main gear-shifting outputmechanism 22. In this case, the sub gear-shifting input mechanism 31 andthe main gear-shifting output mechanism 22 may implement the first powertransmission path. The sub gear-shifting input mechanism 31 may beconnected to the sub gear-shifting drive mechanism 33. Accordingly, thesub gear-shifting input mechanism 31 may transmit the driving powertransmitted through the first power transmission path to the subgear-shifting drive mechanism 33.

The sub gear-shifting input mechanism 31 may include a sub gear-shiftinginput gear 311.

The sub gear-shifting input gear 311 may be connected to the maingear-shifting output member 221. Accordingly, the sub gear-shiftinginput gear 311 may rotate as the main gear-shifting output member 221rotates. The sub gear-shifting input gear 311 receives the driving powerin which the first gear shifting is performed from the maingear-shifting output member 221 and may transmit the received drive tothe sub gear-shifting drive mechanism 33. The sub gear-shifting inputgear 311 may transmit the driving power to the sub gear-shifting drivemechanism 33 using a plurality of gear teeth. For example, the subgear-shifting input gear 311 may be a helical gear. The subgear-shifting input gear 311 may be connected to the main gear-shiftingoutput member 221 by being coupled to the main gear-shifting outputmember 221. In this case, the main gear-shifting output member 221 maytransmit the driving power in which the first gear shifting is performedto the sub gear-shifting input gear 311 and, simultaneously, mayfunction as a rotation shaft of the sub gear-shifting input gear 311.The sub gear-shifting input gear 311 may also be connected to the maingear-shifting output member 221 through a separate shaft. In this case,the shaft to which the sub gear-shifting input gear 311 is coupled maybe coupled to the main gear-shifting output member 221. The shaft towhich the sub gear-shifting input gear 311 is coupled and the maingear-shifting output member 221 may be disposed on the same line.

The sub gear-shifting connection mechanism 32 may be connected to themain gear-shifting part 2. Accordingly, the sub gear-shifting connectionmechanism 32 may implement the second power transmission path throughwhich the driving power in which the first gear shifting is performed istransmitted from the main gear-shifting part 2. The sub gear-shiftingconnection mechanism 32 may be connected to the main gear-shifting part2 so that the second power transmission path is implemented by beingconnected to the main gear-shifting drive mechanism 21. The subgear-shifting connection mechanism 32 may be connected to the subgear-shifting drive mechanism 33. Accordingly, the sub gear-shiftingconnection mechanism 32 may transmit the driving power transmittedthrough the second power transmission path to the sub gear-shiftingdrive mechanism 33.

Thus, since the transmission apparatus 1 of an agricultural workingautomobile according to the first embodiment of the present invention isimplemented so that the main gear-shifting part 2 and the subgear-shifting part 3 are connected to each other through a plurality ofpower transmission paths, the sub gear-shifting connection mechanism 32and the sub gear-shifting input mechanism 31 may share the configurationfor transmitting the driving power to the sub gear-shifting drivemechanism 33. Accordingly, the transmission apparatus 1 of anagricultural working automobile according to the first embodiment of thepresent invention may implement the configuration of the subgear-shifting input mechanism 31 in a simple manner compared to a casein which the main gear-shifting part 2 and the sub gear-shifting part 3are connected to each other through only one power transmission path.Thus, the transmission apparatus 1 of an agricultural working automobileaccording to the first embodiment of the present invention may alleviatecomplexity of the configuration for the sub gear-shifting inputmechanism 31 and also improve ease of manufacturing work.

The sub gear-shifting connection mechanism 32 may be disposed to bepositioned between the main gear-shifting drive mechanism 21 and the subgear-shifting drive mechanism 33. One side of the sub gear-shiftingconnection mechanism 32 may be connected to the main gear-shifting drivemechanism 21. The other side of the sub gear-shifting connectionmechanism 32 may be connected to the sub gear-shifting drive mechanism33. The sub gear-shifting connection mechanism 32 may be a shaft.

The sub gear-shifting drive mechanism 33 will be described in moredetail with reference to FIGS. 3 and 13 as below.

Referring to FIGS. 3 and 4, the sub gear-shifting drive mechanism 33 maybe connected to each of the sub gear-shifting input mechanism 31 and thesub gear-shifting connection mechanism 32. The sub gear-shifting drivemechanism 33 may perform the second gear shifting using one drivingpower selected from the driving power transmitted from the subgear-shifting input mechanism 31 and the driving power transmitted fromthe sub gear-shifting connection mechanism 32. That is, the subgear-shifting drive mechanism 33 may perform the second gear shiftingusing one driving power selected from the driving power transmittedthrough the first power transmission path and the driving powertransmitted through the second power transmission path. The subgear-shifting drive mechanism 33 may perform the second gear shiftingusing one driving power selected by the gear-shifting operation of theoperator.

The sub gear-shifting drive mechanism 33 may include a plurality of subgear-shifting drive gears 331. The sub gear-shifting drive mechanism 33may include a number of sub gear-shifting drive gears 331 correspondingto a second gear-shifting stage performable by the sub gear-shiftingpart 3. For example, when the sub gear-shifting part 3 is implemented toperform the second gear shifting in two stages, the sub gear-shiftingdrive mechanism 33 may include two sub gear-shifting drive gears 331.The sub gear-shifting drive gears 331 are provided to transmit thedriving power using a plurality of gear teeth and, for example, may behelical gears.

One sub gear-shifting drive gear 331 of the sub gear-shifting drivegears 331 is connected to the main gear-shifting drive mechanism 21through the sub gear-shifting connection mechanism 32 so that the subgear-shifting drive mechanism 33 may be connected to the maingear-shifting part 2. In this case, one side of the sub gear-shiftingconnection mechanism 32 may be coupled to one main gear-shifting drivegear 211 of the main gear-shifting drive gears 211, and the other sideof the sub gear-shifting connection mechanism 32 may be coupled to onesub gear-shifting drive gear 331 of the sub gear-shifting drive gears331. That is, the sub gear-shifting connection mechanism 32 may connectthe main gear-shifting drive gear 211 to the sub gear-shifting drivegear 331 in a direct connection manner. Accordingly, the transmissionapparatus 1 of an agricultural working automobile according to the firstembodiment of the present invention may alleviate complexity of theconfiguration of the sub gear-shifting part 3 and reduce manufacturingcosts for the sub gear-shifting part 3 in comparison with a comparativeexample having only one power transmission path.

This is exemplified by the case in which the sub gear-shifting part 3 or13 performs the second gear shifting in two stages as shown in FIGS. 4and 5, and will be described in more detail below in comparison withcomparative examples in which the sub gear-shifting part 13 is connectedto the main gear-shifting part 12 through only one power transmissionpath and an example in which the sub gear-shifting part 3 is connectedto the main gear-shifting part 2 through two power transmission paths.In this case, both the comparative example and the example include twosub gear-shifting drive gears 331 a and 331 b, or 1331 a and 1331 b forthe sub gear-shifting drive mechanism 33 or 133 to perform the secondgear shifting in two stages. First, as shown in FIG. 5, in a case of thecomparative example in which the sub gear-shifting part 13 is connectedto the main gear-shifting part 12 through only one power transmissionpath, the sub gear-shifting drive mechanism 133 receives the drivingpower in which the first gear shifting is performed through only the subgear-shifting input mechanism 131. Accordingly, the sub gear-shiftinginput mechanism 131 needs to include two sub gear-shifting input gears1311 and 1311′ to transmit the driving power in which the first gearshifting is performed to each of the two sub gear-shifting drive gears1331 a and 1331 b. Further, all of the sub gear-shifting drive gears1331 a and 1331 b need to have a function of receiving the driving powerfrom the sub gear-shifting input gears 1311 and 1311′ and transmittingthe driving power to the sub gear-shifting out mechanism 130.Accordingly, all of the sub gear-shifting drive gears 1331 a and 1331 bneed to be implemented to include an input gear for receiving thedriving power and an output gear for transmitting the driving power.

Next, as shown in FIG. 4, in the case of the example in which the subgear-shifting part 3 is connected to the main gear-shifting part 2through two power transmission paths, the sub gear-shifting drivemechanism 33 receives the driving power in which the first gear shiftingis performed through the sub gear-shifting input mechanism 31 and thesub gear-shifting connection mechanism 32. In this case, one subgear-shifting drive gear 331 a of the sub gear-shifting drive gears 331a and 331 b is connected to the sub gear-shifting input mechanism 31 toreceive the driving power in which the first gear shifting is performed.The other one sub gear-shifting drive gear 331 b of the subgear-shifting drive gears 331 a and 331 b is connected to the subgear-shifting connection mechanism 32 to receive the driving power inwhich the first gear shifting is performed. Accordingly, thetransmission apparatus 1 of an agricultural working automobile accordingto the first embodiment of the present invention may provide operatingeffects as described below in comparison with the comparative example.

First, in the transmission apparatus 1 of an agricultural workingautomobile according to the first embodiment of the present invention,since the sub gear-shifting input mechanism 31 needs to have only onesub gear-shifting input gear 311, one sub gear-shifting input gear 1311′(shown in FIG. 5) may be omitted in comparison with the comparativeexample. Accordingly, the transmission apparatus 1 of an agriculturalworking automobile according to the first embodiment of the presentinvention may not only implement the configuration of the subgear-shifting input mechanism 31 in a simple manner but also reducemanufacturing costs for the sub gear-shifting input mechanism 31.

Second, the sub gear-shifting drive gear 331 b, which is connected tothe sub gear-shifting connection mechanism 32, between the subgear-shifting drive gears 331 a and 331 b does not need to have theinput gear for receiving the driving power when compared with thecomparative example Thus, the transmission apparatus 1 of anagricultural working automobile according to the first embodiment of thepresent invention may not only implement the configuration of the subgear-shifting drive mechanism 33 in a simple manner but also reducemanufacturing costs for the sub gear-shifting drive mechanism 33.

Referring to FIGS. 3 and 4, the sub gear-shifting drive gear 331, whichis spaced apart from the main gear-shifting drive mechanism 21 by theshortest distance, of the sub gear-shifting drive gears 331 is connectedto the main gear-shifting drive mechanism 21 through the subgear-shifting connection mechanism 32 so that the sub gear-shiftingdrive mechanism 33 may be connected to the main gear-shifting part 2.The shortest distance is on the basis of the first axis direction (the Xaxis direction). In this case, the sub gear-shifting connectionmechanism 32 may be coupled to each of the sub gear-shifting drive gear331 and the main gear-shifting drive gear 211, which are spaced apartfrom each other by the shortest distance, among the sub gear-shiftingdrive gears 331 and the main gear-shifting drive gears 211.

Accordingly, the transmission apparatus 1 of an agricultural workingautomobile according to the first embodiment of the present inventionmay reduce the length of the sub gear-shifting connection mechanism 32on the basis of the first axis direction (the X axis direction), therebynot only improving drive transmission performance to the subgear-shifting connection mechanism 32 but also reducing manufacturingcosts for the sub gear-shifting connection mechanism 32. Further, in thetransmission apparatus 1 of an agricultural working automobile accordingto the first embodiment of the present invention, the sub gear-shiftingconnection mechanism 32 may connect the sub gear-shifting drive gear 331to the main gear-shifting drive gear 211 in a direct connection manner,thereby implementing the configuration for connecting the subgear-shifting drive gear 331 to the main gear-shifting drive gear 211 ina simple manner. The sub gear-shifting connection mechanism 32 and themain gear-shifting input mechanism 20 may be disposed on the same line.In this case, the sub gear-shifting connection mechanism 32, the maingear-shifting input mechanism 20, and the sub gear-shifting outputmechanism 30 may be disposed on the same line. Accordingly, ease ofmanufacturing work of the transmission apparatus 1 of an agriculturalworking automobile according to the first embodiment of the presentinvention may be improved by improving ease of disposition for the maingear-shifting drive gears 211 and the sub gear-shifting drive gears 331.

Referring to FIGS. 3 and 4, the sub gear-shifting drive mechanism 33 mayinclude at least one sub gear-shifting sleeve 332. The sub gear-shiftingsleeve 332 may be selectively connected to any one of the two subgear-shifting drive gears 331. The sub gear-shifting sleeve 332 may beconnected to the corresponding sub gear-shifting drive gear 331 by beingselectively engaged with any one of the two sub gear-shifting drivegears 331. The sub gear-shifting sleeve 332 may be selectively connectedto any one of the two sub gear-shifting drive gears 331 by thegear-shifting operation of the operator. The sub gear-shifting sleeve332 is coupled to the sub gear-shifting output mechanism 30.Accordingly, the sub gear-shifting sleeve 332 may rotate the subgear-shifting output mechanism 30. In this case, the sub gear-shiftingsleeve 332 may rotate the sub gear-shifting output mechanism 30 whilerotating as the sub gear-shifting drive gear 331 connected to the subgear-shifting sleeve 332 is rotated. The sub gear-shifting sleeve 332may rotate about the sub gear-shifting output mechanism 30 as a rotationshaft. The sub gear-shifting sleeve 332 may be a synchronizer sleeve.The sub gear-shifting drive mechanism 33 may include a required numberof the sub gear-shifting sleeve 332 in accordance with the secondgear-shifting stage to be performed by the sub gear-shifting part 3.

Referring to FIGS. 4, 6, and 10, when the sub gear-shifting part 3performs the second gear shifting in two stages, the sub gear-shiftingdrive mechanism 33 may include the first sub gear-shifting drive gear331 a, the second sub gear-shifting drive gear 331 b, and a first subgear-shifting sleeve 332 a.

The first sub gear-shifting drive gear 331 a may be idly coupled to thesub gear-shifting output mechanism 30. A bearing (not shown) may beinstalled between the first sub gear-shifting drive gear 331 a and thesub gear-shifting output mechanism 30. The first sub gear-shifting drivegear 331 a may be rotated by the driving power provided from the subgear-shifting input mechanism 31. In this case, the first subgear-shifting drive gear 331 a may include a first input gear 3311 a forbeing connected to the sub gear-shifting input mechanism 31 and a firstoutput gear 3312 a for being connected to the first sub gear-shiftingsleeve 332 a. The first input gear 3311 a may be engaged with the subgear-shifting input gear 311. Accordingly, the first sub gear-shiftingdrive gear 331 a may rotate as the sub gear-shifting input gear 311rotates. That is, the first sub gear-shifting drive gear 331 a may berotated by the driving power transmitted through the first powertransmission path. In this case, when the first output gear 3312 a isconnected to the first sub gear-shifting sleeve 332 a, the first subgear-shifting drive gear 331 a is rotated by the driving powertransmitted through the first power transmission path in order to rotatethe first sub gear-shifting sleeve 332 a and the sub gear-shiftingoutput mechanism 30.

The second sub gear-shifting drive gear 331 b may be disposed to bespaced apart from the first sub gear-shifting drive gear 331 a in thefirst axis direction (the X axis direction). The first sub gear-shiftingsleeve 332 a may be disposed between the second sub gear-shifting drivegear 331 b and the first sub gear-shifting drive gear 331 a. The secondsub gear-shifting drive gear 331 b may be disposed between the first subgear-shifting sleeve 332 a and the main gear-shifting part 2. The secondsub gear-shifting drive gear 331 b may be rotated by the driving powerprovided from the sub gear-shifting connection mechanism 32. That is,the second sub gear-shifting drive gear 331 b may be rotated by thedriving power transmitted through the second power transmission path.One side of the sub gear-shifting connection mechanism 32 may be coupledto the second main gear-shifting drive gear 211 b and the other side ofthe sub gear-shifting connection mechanism 32 may be coupled to thesecond sub gear-shifting drive gear 331 b. The second main gear-shiftingdrive gear 211 b and the second sub gear-shifting drive gear 331 b aredisposed to be spaced apart from each other by the shortest distanceamong the main gear-shifting drive gears 211 and the sub gear-shiftingdrive gears 331 on the basis of the first axis direction (the X axisdirection). One side of the sub gear-shifting connection mechanism 32may be coupled to the second drive output gear 2112 b of the second maingear-shifting drive gear 211 b.

The second sub gear-shifting drive gear 331 b may include a secondoutput gear for being connected to the first sub gear-shifting sleeve332 a. In this case, when the second output gear is connected to thefirst sub gear-shifting sleeve 332 a, the second sub gear-shifting drivegear 331 b is rotated by the driving power transmitted through thesecond power transmission path in order to rotate the first subgear-shifting sleeve 332 a.

The first sub gear-shifting sleeve 332 a may be coupled to the subgear-shifting output mechanism 30 so as to be positioned between thefirst sub gear-shifting drive gear 331 a and the second subgear-shifting drive gear 331 b. The first sub gear-shifting sleeve 332 amay be coupled to the sub gear-shifting output mechanism 30 to bemovable in the first axis direction (the X axis direction). Accordingly,the first sub gear-shifting sleeve 332 a may be selectively connected tothe first sub gear-shifting drive gear 331 a or the second subgear-shifting drive gear 331 b to perform the second gear shifting. Inthis case, the first sub gear-shifting sleeve 332 a may be selectivelyconnected to the first sub gear-shifting drive gear 331 a or the secondsub gear-shifting drive gear 331 b while moving along the first axisdirection (the X axis direction) by the gear-shifting operation of theoperator.

Referring to FIGS. 3 and 4, the sub gear-shifting drive mechanism 33 andthe main gear-shifting drive mechanism 21 may be implemented so that thesub gear-shifting drive gear 331, which corresponds to a gear-shiftingstage having the highest frequency of use in the sub gear-shifting part3, and the main gear-shifting drive gear 211, which corresponds to agear-shifting stage having the highest frequency of use in the maingear-shifting part 2, are connected to each other through the subgear-shifting connection mechanism 32. That is, the sub gear-shiftingconnection mechanism 32 may connect the main gear-shifting drive gear211, which corresponds to the gear-shifting stage having the highestfrequency of use in the main gear-shifting part 2, to the subgear-shifting drive gear 331, which corresponds to the gear-shiftingstage having the highest frequency of use in the sub gear-shifting part3, in a direct connection manner. Accordingly, in the transmissionapparatus 1 of an agricultural working automobile according to thepresent invention, when the main gear-shifting part 2 and the subgear-shifting part 3 perform the gear shifting at the gear-shiftingstage having the highest frequency of use and transmit the driving powerthrough the sub gear-shifting connection mechanism 32, a driving powerloss may be reduced and drive transmission performance may be improved.Accordingly, the transmission apparatus 1 of an agricultural workingautomobile according to the present invention may contribute toimproving performance of the agricultural working automobile. Forexample, when the second main gear-shifting drive gear 211 b correspondsto the gear-shifting stage having the highest frequency of use in themain gear-shifting part 2 and the second sub gear-shifting drive gear331 b corresponds to the gear-shifting stage having the highestfrequency of use in the sub gear-shifting part 3, the sub gear-shiftingconnection mechanism 32 may connect the second main gear-shifting drivegear 211 b to the second sub gear-shifting drive gear 331 b in a directconnection manner.

Referring to FIGS. 6 to 9, when the first sub gear-shifting sleeve 332 ais connected to the first sub gear-shifting drive gear 331 a, the firstsub gear-shifting sleeve 332 a may receive the driving power in whichthe first gear shifting is performed through the sub gear-shifting inputmechanism 31. That is, the first sub gear-shifting sleeve 332 a mayreceive the driving power in which the first gear shifting is performedthrough the first power transmission path. Accordingly, the subgear-shifting drive mechanism 33 may perform the second gear shiftingusing the first sub gear-shifting input mechanism 31, the first subgear-shifting drive gear 331 a, and the first sub gear-shifting sleeve332 a and output the driving power in which the second gear shifting isperformed through the sub gear-shifting output mechanism 30. In thiscase, for all first gear-shifting stages performable by the maingear-shifting part 2, the first sub gear-shifting sleeve 332 a mayreceive the driving power in which the first gear shifting is performedthrough the first power transmission path.

This will be described in detail with reference to FIGS. 6 to 9 asbelow. Numbers in the circles indicated in the main gear-shifting part 2in FIGS. 6 to 9 exemplify the first gear shifting stage, andalphabetical letters in the circle indicated in the sub gear-shiftingpart 3 exemplify the second gear-shifting stage. As shown in FIGS. 6 to9, when the first sub gear-shifting sleeve 332 a is connected to thefirst sub gear-shifting drive gear 331 a, the second gear shifting maybe performed at a low stage.

First, when the main gear-shifting part 2 performs the first gearshifting at a first speed stage as shown in FIG. 6, the first maingear-shifting sleeve 212 a is connected to the first main gear-shiftingdrive gear 211 a. Accordingly, the driving power provided from the maingear-shifting input mechanism 20 is sequentially transmitted through thefirst main gear-shifting sleeve 212 a, the first main gear-shiftingdrive gear 211 a, the first main gear-shifting output gear 222 a, themain gear-shifting output member 221, the sub gear-shifting input gear311, the first sub gear-shifting drive gear 331 a, and the first subgear-shifting sleeve 332 a to perform the first gear shifting and thesecond gear-shifting and may be output to the second external devicethrough the sub gear-shifting output mechanism 30. In this case, thesecond main gear-shifting sleeve 212 b is in a neutral state in whichthe second main gear-shifting sleeve 212 b is not connected to both thethird main gear-shifting drive gear 211 c and the fourth maingear-shifting drive gear 211 d.

Next, when the main gear-shifting part 2 performs the first gearshifting at a second speed stage as shown in FIG. 7, the first maingear-shifting sleeve 212 a is connected to the second main gear-shiftingdrive gear 211 b. Accordingly, the driving power provided from the maingear-shifting input mechanism 20 is sequentially transmitted through thefirst main gear-shifting sleeve 212 a, the second main gear-shiftingdrive gear 211 b, the second main gear-shifting output gear 222 b, themain gear-shifting output member 221, the sub gear-shifting input gear311, the first sub gear-shifting drive gear 331 a, and the first subgear-shifting sleeve 332 a to perform the first gear shifting and thesecond gear-shifting and may be output to the second external devicethrough the sub gear-shifting output mechanism 30. In this case, thesecond main gear-shifting sleeve 212 b is in a neutral state in whichthe second main gear-shifting sleeve 212 b is not connected to both thethird main gear-shifting drive gear 211 c and the fourth maingear-shifting drive gear 211 d.

Next, when the main gear-shifting part 2 performs the first gearshifting at a third speed stage as shown in FIG. 8, the second maingear-shifting sleeve 212 b is connected to the third main gear-shiftingdrive gear 211 c. Accordingly, the driving power provided from the maingear-shifting input mechanism 20 is sequentially transmitted through thesecond main gear-shifting sleeve 212 b, the third main gear-shiftingdrive gear 211 c, the third main gear-shifting output gear 222 c, themain gear-shifting output member 221, the sub gear-shifting input gear311, the first sub gear-shifting drive gear 331 a, and the first subgear-shifting sleeve 332 a to perform the first gear shifting and thesecond gear shifting and may be output to the second external devicethrough the sub gear-shifting output mechanism 30. In this case, thefirst main gear-shifting sleeve 212 a is in a neutral state in which thefirst main gear-shifting sleeve 212 a is not connected to both the firstmain gear-shifting drive gear 211 a and the second main gear-shiftingdrive gear 211 b.

Next, when the main gear-shifting part 2 performs the first gearshifting at a fourth speed stage as shown in FIG. 9, the second maingear-shifting sleeve 212 b is connected to the fourth main gear-shiftingdrive gear 211 d. Accordingly, the driving power provided from the maingear-shifting input mechanism 20 is sequentially transmitted through thesecond main gear-shifting sleeve 212 b, the fourth main gear-shiftingdrive gear 211 d, the fourth main gear-shifting output gear 222 d, themain gear-shifting output member 221, the sub gear-shifting input gear311, the first sub gear-shifting drive gear 331 a, and the first subgear-shifting sleeve 332 a to perform the first gear shifting and thesecond gear shifting and may be output to the second external devicethrough the sub gear-shifting output mechanism 30. In this case, thefirst main gear-shifting sleeve 212 a is in a neutral state in which thefirst main gear-shifting sleeve 212 a is not connected to both the firstmain gear-shifting drive gear 211 a and the second main gear-shiftingdrive gear 211 b.

Referring to FIGS. 10 to 13, when the first sub gear-shifting sleeve 332a is connected to the second sub gear-shifting drive gear 331 b, thefirst sub gear-shifting sleeve 332 a may receive the driving power inwhich the first gear shifting is performed through the sub gear-shiftingconnection mechanism 32. That is, the first sub gear-shifting sleeve 332a may receive the driving power in which the first gear shifting isperformed through the second power transmission path. Accordingly, thesub gear-shifting drive mechanism 33 may perform the second gearshifting using the first sub gear-shifting connection mechanism 32, thesecond sub gear-shifting drive gear 331 b, and the first subgear-shifting sleeve 332 a and output the driving power in which thesecond gear shifting is performed through the sub gear-shifting outputmechanism 30. In this case, for all first gear-shifting stagesperformable by the main gear-shifting part 2, the first subgear-shifting sleeve 332 a may receive the driving power in which thefirst gear shifting is performed through the second power transmissionpath.

This will be described in detail with reference to FIGS. 10 to 13 asbelow. Numbers in the circles indicated in the main gear-shifting part 2in FIGS. 10 to 13 exemplify the first gear-shifting stage, andalphabetical letters in the circle indicated in the sub gear-shiftingpart 3 exemplify the second gear-shifting stage. As shown in FIGS. 10 to13, when the first sub gear-shifting sleeve 332 a is connected to thesecond sub gear-shifting drive gear 331 b, the second gear shifting maybe performed at a high stage.

First, when the main gear-shifting part 2 performs the first gearshifting at a first speed stage as shown in FIG. 10, the first maingear-shifting sleeve 212 a is connected to the first main gear-shiftingdrive gear 211 a. Accordingly, the driving power provided from the maingear-shifting input mechanism 20 is sequentially transmitted through thefirst main gear-shifting sleeve 212 a, the first main gear-shiftingdrive gear 211 a, the first main gear-shifting output gear 222 a, themain gear-shifting output member 221, the second main gear-shiftingoutput gear 222 b, the second main gear-shifting drive gear 211 b, thesub gear-shifting connection mechanism 32, the second sub gear-shiftingdrive gear 331 b, and the first sub gear-shifting sleeve 332 a toperform the first gear shifting and the second gear shifting and may beoutput to the second external device through the sub gear-shiftingoutput mechanism 30. In this case, the second main gear-shifting sleeve212 b is in a neutral state in which the second main gear-shiftingsleeve 212 b is not connected to both the third main gear-shifting drivegear 211 c and the fourth main gear-shifting drive gear 211 d.

Next, when the main gear-shifting part 2 performs the first gearshifting to a second speed stage as shown in FIG. 11, the first maingear-shifting sleeve 212 a is connected to the second main gear-shiftingdrive gear 211 b. Accordingly, the driving power provided from the maingear-shifting input mechanism 20 is sequentially transmitted through thefirst main gear-shifting sleeve 212 a, the second main gear-shiftingdrive gear 211 b, the sub gear-shifting connection mechanism 32, thesecond sub gear-shifting drive gear 331 b, and the first subgear-shifting sleeve 332 a to perform the first gear shifting and thesecond gear shifting and may be output to the second external devicethrough the sub gear-shifting output mechanism 30. In this case, thesecond main gear-shifting sleeve 212 b is in a neutral state in whichthe second main gear-shifting sleeve 212 b is not connected to both thethird main gear-shifting drive gear 211 c and the fourth maingear-shifting drive gear 211 d.

Next, when the main gear-shifting part 2 performs the first gearshifting to a third speed stage as shown in FIG. 12, the second maingear-shifting sleeve 212 b is connected to the third main gear-shiftingdrive gear 211 c. Accordingly, the driving power provided from the maingear-shifting input mechanism 20 is sequentially transmitted through thesecond main gear-shifting sleeve 212 b, the third main gear-shiftingdrive gear 211 c, the third main gear-shifting output gear 222 c, themain gear-shifting output member 221, the second main gear-shiftingoutput gear 222 b, the second main gear-shifting drive gear 211 b, thesub gear-shifting connection mechanism 32, the second sub gear-shiftingdrive gear 331 b, and the first sub gear-shifting sleeve 332 a toperform the first gear shifting and the second gear shifting and may beoutput to the second external device through the sub gear-shiftingoutput mechanism 30. In this case, the first main gear-shifting sleeve212 a is in a neutral state in which the first main gear-shifting sleeve212 a is not connected to both the first main gear-shifting drive gear211 a and the second main gear-shifting drive gear 211 b.

Next, when the main gear-shifting part 2 performs the first gearshifting at a fourth speed stage as shown in FIG. 13, the second maingear-shifting sleeve 212 b is connected to the fourth main gear-shiftingdrive gear 211 d. Accordingly, the driving power provided from the maingear-shifting input mechanism 20 is sequentially transmitted through thesecond main gear-shifting sleeve 212 b, the fourth main gear-shiftingdrive gear 211 d, the fourth main gear-shifting output gear 222 d, themain gear-shifting output member 221, the second main gear-shiftingoutput gear 222 b, the second main gear-shifting drive gear 211 b, thesub gear-shifting connection mechanism 32, the second sub gear-shiftingdrive gear 331 b, and the first sub gear-shifting sleeve 332 a toperform the first gear shifting and the second gear shifting and may beoutput to the second external device through the sub gear-shiftingoutput mechanism 30. In this case, the first main gear-shifting sleeve212 a is in a neutral state in which the first main gear-shifting sleeve212 a is not connected to both the first main gear-shifting drive gear211 a and the second main gear-shifting drive gear 211 b.

Although the embodiment in which the main gear-shifting part 2 performsthe first gear shifting in four stages is illustrated in FIGS. 6 to 13,those skilled in the art may easily derive embodiments in which the maingear-shifting part 2 performs the first gear shifting in differentgear-shifting stages rather than the four stages such as three stages,five stages, six stages, seven stages, eight stages, or the like fromthe embodiment.

Here, gear-shifting ranges of the transmission apparatus of anagricultural working automobile according to the first embodiment of thepresent invention may be adjusted according to the diameter of the firstinput gear 3311 a of the first sub gear-shifting drive gear 331 a andthe diameter of the sub gear-shifting input gear 311.

For example, like in a configuration of the embodiment described inFIGS. 4 and 6 to 13, a diameter ratio of the first input gear 3311 a ofthe first sub gear-shifting drive gear 331 a to the sub gear-shiftinginput gear 311 may be implemented to be greater than a diameter ratio ofthe second main gear-shifting drive gear 2112 b of the second maingear-shifting drive gear 211 b to the second main gear-shifting outputgear 222 b. In this case, the first sub gear-shifting drive gear 331 arotates at a slower rotational speed than the second sub gear-shiftingdrive gear 331 b having the same rotational speed as a rotational speedof the second main gear-shifting drive gear 211 b. That is, in a case inwhich the first sub gear-shifting sleeve 332 a is connected to the firstsub gear-shifting drive gear 331 a which is rotated by the driving powertransmitted through the first power transmission path passing throughthe sub gear-shifting input mechanism 31, the gear shifting is performedat a slower speed than in a case in which the first sub gear-shiftingsleeve 332 a is connected to the second sub gear-shifting drive gear 331b which is rotated by the driving power transmitted through the secondpower transmission path passing through the sub gear-shifting connectionmechanism 32.

For example, unlike in the configuration of the embodiment described inFIGS. 4 and 6 to 13, although not shown in the drawings, the diameterratio of the first input gear 3311 a of the first sub gear-shiftingdrive gear 331 a to the sub gear-shifting input gear 311 may beimplemented to be smaller than the diameter ratio of the second maingear-shifting drive gear 2112 b of the second main gear-shifting drivegear 211 b to the second main gear-shifting output gear 222 b. In thiscase, the first sub gear-shifting drive gear 331 a rotates at a greaterrotational speed than the second sub gear-shifting drive gear 331 bhaving the same rotational speed as the rotational speed of the secondmain gear-shifting drive gear 211 b. That is, in the case in which thefirst sub gear-shifting sleeve 332 a is connected to the first subgear-shifting drive gear 331 a which is rotated by the driving powertransmitted through the first power transmission path passing throughthe sub gear-shifting input mechanism 31, the gear shifting is performedat a faster speed than in the case in which the first sub gear-shiftingsleeve 332 a is connected to the second sub gear-shifting drive gear 331b which is rotated by the driving power transmitted through the secondpower transmission path passing through the sub gear-shifting connectionmechanism 32.

Referring to FIGS. 14 to 16, the sub gear-shifting part 3 according to amodified embodiment of the present invention may further include a thirdsub gear-shifting drive gear 331 c and a second sub gear-shifting sleeve332 b.

The third sub gear-shifting drive gear 331 c is connected to the firstsub gear-shifting drive gear 331 a. Accordingly, the third subgear-shifting drive gear 331 c may rotate as the first sub gear-shiftingdrive gear 331 a rotates. The third sub gear-shifting drive gear 331 cmay include a third input gear 3311 c for being engaged with the firstsub gear-shifting drive gear 331 a and a third output gear 3312 c forbeing engaged with the second sub gear-shifting sleeve 332 b. In thiscase, the first sub gear-shifting drive gear 331 a may include a firstsub output gear 3313 a for being engaged with the third input gear 3311c. Accordingly, when the first sub gear-shifting drive gear 331 arotates, the third sub gear-shifting drive gear 331 c may rotate throughthe engagement between the first sub output gear 3313 a and the thirdinput gear 3311 c. In this case, when the third output gear 3312 c is ina state of being connected to the second sub gear-shifting sleeve 332 b,the third sub gear-shifting drive gear 331 c is rotated by the first subgear-shifting drive gear 331 a to rotate the second sub gear-shiftingsleeve 332 b.

The second sub gear-shifting sleeve 332 b is selectively connected tothe third sub gear-shifting drive gear 331 c for the second gearshifting. In this case, the second sub gear-shifting sleeve 332 b may beselectively connected to the third sub gear-shifting drive gear 331 c bythe gear-shifting operation of the operator while moving along the firstaxis direction (the X axis direction). The second sub gear-shiftingsleeve 332 b is connected to the sub gear-shifting output mechanism 30.Accordingly, when the second sub gear-shifting sleeve 332 b is connectedto the third sub gear-shifting drive gear 331 c, the sub gear-shiftingoutput mechanism 30 may output the driving power provided from thesecond sub gear-shifting sleeve 332 b. In this case, the first subgear-shifting sleeve 332 a is in a neutral state in which the first subgear-shifting sleeve 332 a is not connected to both the first subgear-shifting drive gear 331 a and the second sub gear-shifting drivegear 331 b. When the first sub gear-shifting sleeve 332 a is connectedto the first sub gear-shifting drive gear 331 a or the second subgear-shifting drive gear 331 b, the sub gear-shifting output mechanism30 may output the driving power provided from the first subgear-shifting sleeve 332 a. In this case, the second sub gear-shiftingsleeve 332 b is in a neutral state which is not connected to the thirdsub gear-shifting drive gear 331 c.

As described above, since the sub gear-shifting part 3 may perform thesecond gear shifting in three stages, the transmission apparatus 1 of anagricultural working automobile according to the first embodiment of thepresent invention may be implemented so that the agricultural workingautomobile may perform work in accordance with various work environmentsthrough more detailed gear shifting. Accordingly, the transmissionapparatus 1 of an agricultural working automobile according to the firstembodiment of the present invention may not only improve efficiency ofthe work using the agricultural working automobile but also contributeto increasing utilization of the agricultural working automobile forvarious working environments.

The sub gear-shifting drive mechanism 33 may include a connection shaft333, a first connection gear 334, and a second connection gear 335.

The connection shaft 333 connects the second sub gear-shifting sleeve332 b to the first connection gear 334. The second sub gear-shiftingsleeve 332 b and the first connection gear 334 may be coupled to theconnection shaft 333 at a position spaced apart from each other in thefirst axis direction (the X axis direction). Accordingly, when thesecond sub gear-shifting sleeve 332 b rotates, the connection shaft 333may rotate the first connection gear 334 while rotating as the secondsub gear-shifting sleeve 332 b rotates. The connection shaft 333 may bedisposed parallel to the sub gear-shifting output mechanism 30. Thethird sub gear-shifting drive gear 331 c may be idly coupled to theconnection shaft 333. A bearing (not shown) may be installed between thethird sub gear-shifting drive gear 331 c and the connection shaft 333.

The first connection gear 334 rotates as the connection shaft 333rotates. The first connection gear 334 may be engaged with the secondconnection gear 335. Accordingly, the first connection gear 334 mayrotate the second connection gear 335 while rotating as the connectionshaft 333 rotates. The first connection gear 334 may transmit thedriving power to the second connection gear 335 using a plurality ofgear teeth. For example, the first connection gear 334 may be a helicalgear.

The second connection gear 335 is coupled to the sub gear-shiftingoutput mechanism 30. The second connection gear 335 may be coupled tothe sub gear-shifting output mechanism 30 at a position spaced apartfrom the first sub gear-shifting drive gear 331 a in the first axisdirection (the X axis direction). The second connection gear 335 may beengaged with the first connection gear 334. Accordingly, the secondconnection gear 335 may rotate the sub gear-shifting output mechanism 30while rotating as the first connection gear 334 rotates. The secondconnection gear 335 may receive the driving power from the firstconnection gear 334 using a plurality of gear teeth. For example, thesecond connection gear 335 may be a helical gear.

The second connection gear 335 may be formed to have a greater diameterthan the first connection gear 334. Accordingly, deceleration may beachieved in a process of transmitting the driving power from the firstconnection gear 334 to the second connection gear 335. In this case, asshown in FIG. 15, when the second sub gear-shifting sleeve 332 b isconnected to the third sub gear-shifting drive gear 331 c, the secondgear shifting may be performed at a low stage. When the first subgear-shifting sleeve 332 a is connected to the second sub gear-shiftingdrive gear 331 b, the second gear shifting may be performed at a highstage. When the first sub gear-shifting sleeve 332 a is connected to thefirst sub gear-shifting drive gear 331 a, the second gear shifting maybe performed at a middle stage. In this case, the high stage is thefastest speed and the low stage is the slowest speed. The middle stageis the middle speed between the high stage and the low stage.

As shown in FIG. 15, when the second sub gear-shifting sleeve 332 b isconnected to the third sub gear-shifting drive gear 331 c, the secondsub gear-shifting sleeve 332 b may receive the driving power in whichthe first gear shifting is performed through the first powertransmission path. In this case, for all first gear-shifting stagesperformable by the main gear-shifting part 2, the second subgear-shifting sleeve 332 b may receive the driving power in which thefirst gear shifting is performed through the first power transmissionpath. The driving power transmitted through the first power transmissionpath is sequentially transmitted through the sub gear-shifting inputgear 311, the first sub gear-shifting drive gear 331 a, the third subgear-shifting drive gear 331 c, the second sub gear-shifting sleeve 332b, the connection shaft 333, the first connection gear 334, and thesecond connection gear 335 to perform the second gear-shifting and maybe output to the second external device through the sub gear-shiftingoutput mechanism 30.

Here, as shown in FIG. 15, the sub gear-shifting drive mechanism 33 maybe disposed so that the second sub gear-shifting sleeve 332 b ispositioned between the third sub gear-shifting drive gear 331 c and thefirst connection gear 334.

Meanwhile, as shown in FIG. 16, the sub gear-shifting drive mechanism 33may be disposed so that the third sub gear-shifting drive gear 331 c ispositioned between the second sub gear-shifting sleeve 332 b and thefirst connection gear 334. In this case, the second sub gear-shiftingsleeve 332 b and the third sub gear-shifting drive gear 331 c may bedisposed so that at least parts thereof overlap the first subgear-shifting sleeve 332 a and the first sub gear-shifting drive gear331 a.

Accordingly, since the transmission apparatus 1 of an agriculturalworking automobile according to the first embodiment of the presentinvention may be implemented such that a length thereof based on thefirst axis direction (the X axis direction) is reduced, an installationarea occupied by the agricultural working automobile based on the firstaxis direction (X axis direction) may be reduced. Accordingly, thetransmission apparatus 1 of an agricultural working automobile accordingto the first embodiment of the present invention may contribute toimproving utilization of spaces for installing and disposing variousdevices on the agricultural working automobile. Referring to FIG. 16,the second sub gear-shifting sleeve 332 b and the third subgear-shifting drive gear 331 c may be disposed on bottoms of the firstsub gear-shifting sleeve 332 a and the first sub gear-shifting drivegear 331 a so as to overlap the first sub gear-shifting sleeve 332 a andthe first sub gear-shifting drive gear 331 a.

Referring to FIGS. 17 and 18, in the transmission apparatus 1 of anagricultural working automobile according to the first embodiment of thepresent invention, a through hole 221 a may be formed in the maingear-shifting output member 221. The through hole 221 a may be formed topass through the main gear-shifting output member 221. Accordingly, apower transmission shaft 200 of the agricultural working automobile maybe installed in the main gear-shifting output member 221. The powertransmission shaft 200 is installed to traverse the inside of the maingear-shifting output member 221 through the through hole 221 a totransmit a predetermined drive. Accordingly, the transmission apparatus1 of a working automobile according to the first embodiment of thepresent invention may contribute to further improving utilization of thespaces for installing and disposing various devices on the agriculturalworking automobile.

Referring to FIGS. 19 and 20, a transmission apparatus 1 of anagricultural working automobile according to a modified first embodimentof the present invention may include the first gear-shifting part 110and the second gear-shifting part 120. Since the first gear-shiftingpart 110 and the second gear-shifting part 120 are substantially thesame as those described in the transmission apparatus 1 of anagricultural working automobile according to the first embodiment of thepresent invention, the following description will focus on parts withdifferences. Here, description will be made on the basis of anembodiment in which a main gear-shifting part 2 of the firstgear-shifting part 110 and a sub gear-shifting part 3 of the secondgear-shifting part 120 are connected to each other through two powertransmission paths.

A main gear-shifting output mechanism 22 of the main gear-shifting part2 may be connected to a sub gear-shifting drive mechanism 33 of the subgear-shifting part 3. Accordingly, the main gear-shifting outputmechanism 22 may implement the first power transmission path. One sideof a main gear-shifting output member 221 of the main gear-shiftingoutput mechanism 22 may be coupled to a main gear-shifting output gears222 of the main gear-shifting output mechanism 22, and the other side ofthe main gear-shifting output member 221 of the main gear-shiftingoutput mechanism 22 may be coupled to one of the sub gear-shifting drivegears 331 of the sub gear-shifting drive mechanism 33. Accordingly, thesub gear-shifting drive mechanism 33 may receive the driving power fromthe main gear-shifting output mechanism 22 through the maingear-shifting output member 221.

A main gear-shifting drive mechanism 21 of the main gear-shifting part 2may be connected to a sub gear-shifting input mechanism 31 of the subgear-shifting part 3. Accordingly, the sub gear-shifting input mechanism31 may implement the second power transmission path. A sub gear-shiftingconnection mechanism 32 of the sub gear-shifting part 3 may connect themain gear-shifting drive mechanism 21 to the sub gear-shifting inputmechanism 31. In this case, the sub gear-shifting input mechanism 31 andthe sub gear-shifting connection mechanism 32 may implement the secondpower transmission path. One side of the sub gear-shifting connectionmechanism 32 may be coupled to one of the main gear-shifting drive gears211 of the main gear-shifting drive mechanism 21, and the other side ofthe sub gear-shifting connection mechanism 32 may be coupled to a subgear-shifting input gear 311 of the sub gear-shifting input mechanism31. Accordingly, the sub gear-shifting input mechanism 31 receives thedriving power from the main gear-shifting drive mechanism 21 through thesub gear-shifting connection mechanism 32.

A sub gear-shifting input gear 311 of the sub gear-shifting inputmechanism 31 may be connected to the sub gear-shifting connectionmechanism 32. Accordingly, the sub gear-shifting input gear 311 mayrotate as the sub gear-shifting connection mechanism 32 rotates. The subgear-shifting input gear 311 receives the driving power in which thefirst gear shifting is performed from the sub gear-shifting connectionmechanism 32 and may transmit the received drive to the subgear-shifting drive mechanism 33. In this case, the sub gear-shiftingconnection mechanism 32 may transmit the driving power in which thefirst gear shifting is performed to the sub gear-shifting input gear311, and simultaneously, may function as a rotation shaft of the subgear-shifting input gear 311.

The sub gear-shifting drive mechanism 33 may perform the second gearshifting using the driving power transmitted through one powertransmission path selected from the driving power transmitted throughthe first power transmission path and the driving power transmittedthrough the second power transmission path. The sub gear-shifting drivemechanism 33 may be connected to each of the main gear-shifting outputmechanism 22 and the sub gear-shifting input mechanism 31. Thus, the subgear-shifting drive mechanism 33 may receive the driving power throughthe first power transmission path implemented by the main gear-shiftingoutput mechanism 22, and the driving power through the second powertransmission path implemented by the sub gear-shifting connectionmechanism 32. In this case, the sub gear-shifting drive mechanism 33 mayperform the second gear shifting using one driving power selected fromthe driving power transmitted from the main gear-shifting outputmechanism 22 and the driving power transmitted from the subgear-shifting input mechanism 31.

The sub gear-shifting drive mechanism 33 may be connected to the subgear-shifting output mechanism 30. The sub gear-shifting outputmechanism 30 may be rotated by the driving power in which the secondgear shifting is performed by the sub gear-shifting drive mechanism 33.The sub gear-shifting output mechanism 30 may be connected to the secondexternal device. Accordingly, the sub gear-shifting part 3 may outputthe driving power, in which the second gear shifting is performed afterperforming the first gear shifting, to the second external devicethrough the sub gear-shifting output mechanism 30. The sub gear-shiftingoutput mechanism 30 and the main gear-shifting output member 221 may bedisposed on the same line.

One sub gear-shifting drive gear 331 of the sub gear-shifting drivegears 331 is connected to the main gear-shifting output mechanism 22through the main gear-shifting output member 221 so that the subgear-shifting drive mechanism 33 may be connected to the maingear-shifting part 2. In this case, one side of the main gear-shiftingoutput member 221 may be coupled to one main gear-shifting output gear222 of the main gear-shifting output gears 222, and the other side ofthe main gear-shifting output member 221 may be coupled to one subgear-shifting drive gear 331 of the sub gear-shifting drive gears 331.That is, the main gear-shifting output member 221 may connect the maingear-shifting output gear 222 to the sub gear-shifting drive gear 331 ina direct connection manner. The sub gear-shifting drive gear 331, whichis spaced apart from the main gear-shifting output mechanism 22 by theshortest distance, of the sub gear-shifting drive gears 331 is connectedto the main gear-shifting output member 221 so that the subgear-shifting drive mechanism 33 may be connected to the maingear-shifting part 2. The shortest distance is on the basis of the firstaxis direction (the X axis direction).

The sub gear-shifting drive mechanism 33 may include a first subgear-shifting drive gear 331 a which is rotated by the driving powerprovided from the sub gear-shifting input mechanism 31, a second subgear-shifting drive gear 331 b which is rotated by the driving powerprovided from the main gear-shifting output mechanism 22, and a firstsub gear-shifting sleeve 332 a selectively connected to the first subgear-shifting drive gear 331 a or the second sub gear-shifting drivegear 331 b for the second gear shifting.

The first sub gear-shifting drive gear 331 a may be connected to the subgear-shifting input mechanism 31. The sub gear-shifting connectionmechanism 32 may be coupled to the sub gear-shifting input mechanism 31.Accordingly, when the first sub gear-shifting sleeve 332 a is connectedto the sub gear-shifting input mechanism 31, the first sub gear-shiftingsleeve 332 a may receive the driving power in which the first gearshifting is performed through the sub gear-shifting input mechanism 31and the sub gear-shifting connection mechanism 32. That is, the firstsub gear-shifting sleeve 332 a may receive the driving power in whichthe first gear shifting is performed through the second powertransmission path.

The second sub gear-shifting drive gear 331 b may be coupled to the maingear-shifting output member 221. Accordingly, when the first subgear-shifting sleeve 332 a is connected to the second sub gear-shiftingdrive gear 331 a, the first sub gear-shifting sleeve 332 a may receivethe driving power in which the first gear shifting is performed throughthe main gear-shifting output member 221 coupled to the maingear-shifting output mechanism 22. That is, the first sub gear-shiftingsleeve 332 a may receive the driving power in which the first gearshifting is performed through the first power transmission path.

Referring to FIGS. 21 and 22, the transmission apparatus 1 of anagricultural working automobile according to the modified firstembodiment of the present invention may be implemented to include thesub gear-shifting part 3 according to the above-described modifiedembodiment of the present invention. In this case, the sub gear-shiftingpart 3 may include the third sub gear-shifting drive gear 331 c, thesecond sub gear-shifting sleeve 332 b, the connection shaft 333, thefirst connection gear 334, and the second connection gear 335. This issubstantially the same as that described in the sub gear-shifting part 3according to the above-described modified embodiment of the presentinvention, and thus a detailed description thereof will be omitted.

Second Embodiment

A transmission apparatus 1 of an agricultural working automobileaccording to a second embodiment of the present invention may includethe first gear-shifting part 110 and the second gear-shifting part 120.In the transmission apparatus 1 of an agricultural working automobileaccording to the second embodiment of the present invention, since thefirst gear-shifting part 110 and the second gear-shifting part 120 aresubstantially the same as those described in the first embodiment, thefollowing description will focus on parts with differences.

Referring to FIGS. 23 to 25, the first gear-shifting part 110 mayinclude the main gear-shifting part 2 and an ultra-low speedgear-shifting part 4.

The main gear-shifting part 2 performs the first gear shifting to adjusta speed of the agricultural working automobile. Since the maingear-shifting part 2 coincides substantially with that described in thefirst embodiment, the following description will focus on parts withdifferences. The main gear-shifting part 2 may be connected to each ofthe ultra-low speed gear-shifting part 4 and the sub gear-shifting part3. Accordingly, the main gear-shifting part 2 may output the drivingpower in which the first gear shifting is performed to each of theultra-low speed gear-shifting part 4 and the sub gear-shifting part 3.The main gear-shifting part 2 may include the main gear-shifting drivemechanism 21 and the main gear-shifting output mechanism 22.

The main gear-shifting output mechanism 22 may be connected to each ofthe main gear-shifting drive mechanism 21 and the ultra-low speedgear-shifting part 4. The main gear-shifting output mechanism 22 mayinclude the main gear-shifting output member 221 and the maingear-shifting output gears 222.

The main gear-shifting output member 221 may be connected to theultra-low speed gear-shifting part 4. Accordingly, the maingear-shifting output member 221 may output the driving power in whichthe first gear shifting is performed to the ultra-low speedgear-shifting part 4. The main gear-shifting output member 221 mayfunction as one of the power transmission paths for the maingear-shifting part 2 to output the driving power in which the first gearshifting is performed

Referring to FIGS. 23 and 25, the ultra-low speed gear-shifting part 4may be installed between the main gear-shifting part 2 and the secondgear-shifting part 120. The ultra-low speed gear-shifting part 4 may beinstalled between the main gear-shifting part 2 and the secondgear-shifting part 120 on the basis of the first axis direction (the Xaxis direction). The ultra-low speed gear-shifting part 4 may performone gear shifting selected from normal gear shifting and ultra-low speedgear shifting on the driving power transmitted from the maingear-shifting part 2. The selection of either one gear shifting of thenormal gear shifting and the ultra-low speed gear shifting may beperformed by the gear-shifting operation of the operator. When thenormal gear shifting is selected, the ultra-low speed gear-shifting part4 may output the driving power transmitted from the main gear-shiftingpart 2 to the second gear-shifting part 120 as it is. When the ultra-lowspeed gear shifting is selected, the ultra-low speed gear-shifting part4 may perform the gear shifting on the driving power transmitted fromthe main gear-shifting part 2 at an ultra-low speed and output to thesecond gear-shifting part 120. When the ultra-low speed gear-shiftingpart 4 is implemented to be connected to the sub gear-shifting part 3 ofthe second gear-shifting part 120, the ultra-low speed gear-shiftingpart 4 may perform one gear shifting selected from the normal gearshifting and ultra-low speed gear shifting on the driving powertransmitted from the main gear-shifting part 2 and output to the subgear-shifting part 3.

The ultra-low speed gear-shifting part 4 may include an ultra-low speedgear-shifting mechanism 41.

The ultra-low speed gear-shifting mechanism 41 performs the ultra-lowspeed gear shifting on the driving power transmitted from the maingear-shifting part 2. The ultra-low speed gear-shifting mechanism 41 maybe positioned between the main gear-shifting drive mechanism 21 and thesub gear-shifting drive mechanism 33. The ultra-low speed gear-shiftingmechanism 41 may include a first gear-shifting gear 412, a secondgear-shifting gear 413, and a coupling member 414.

The first gear-shifting gear 412 may be coupled to the coupling member414. The first gear-shifting gear 412 may be formed to have a greaterdiameter than the second gear-shifting gear 413. The first gear-shiftinggear 412 may receive the driving power using a plurality of gear teeth.For example, the first gear-shifting gear 412 may be a helical gear.

The second gear-shifting gear 413 may be coupled to the coupling member414. The second gear-shifting gear 413 and the first gear-shifting gear412 may be coupled to the coupling member 414 at a position spaced apartfrom each other on the basis of the first axis direction (the X axisdirection). When the first gear-shifting gear 412 rotates the couplingmember 414 while rotating, the second gear-shifting gear 413 may rotateas the coupling member 414 rotates. That is, the second gear-shiftinggear 413 may rotate as the first gear-shifting gear 412 rotates. Thesecond gear-shifting gear 413 may be formed to have a smaller diameterthan the first gear-shifting gear 412. The second gear-shifting gear 413may receive the driving power using a plurality of gear teeth. Forexample, the second gear-shifting gear 413 may be a helical gear.

The coupling member 414 may function as a rotation shaft of the firstgear-shifting gear 412 and the second gear-shifting gear 413. The firstgear-shifting gear 412 and the second gear-shifting gear 413 may rotateabout the coupling member 414 as a rotation shaft.

The ultra-low speed gear-shifting part 4 may include an ultra-low speedinput gear 42, an ultra-low speed output gear 43, and an ultra-low speedsleeve 44.

The ultra-low speed input gear 42 may be connected to each of the maingear-shifting part 2 and the ultra-low speed gear-shifting mechanism 41.The ultra-low speed input gear 42 may be connected to the maingear-shifting output mechanism 22. Accordingly, the ultra-lowshiftingspeed input gear 42 may be rotated by the driving power transmittedthrough the main gear-output mechanism 22. In this case, the ultra-lowspeed gear-shifting mechanism 41 may be connected to the ultra-low speedinput gear 42. Accordingly, the ultra-low speed gear-shifting mechanism41 may perform the ultra-low speed gear shifting on the driving powertransmitted through the ultra-low speed input gear 42.

The ultra-low speed input gear 42 may be connected to the maingear-shifting output mechanism 22 by being coupled to the maingear-shifting output member 221. The ultra-low speed input gear 42 maybe connected to the first gear-shifting gear 412. The ultra-low speedinput gear 42 may be connected to the first gear-shifting gear 412 bybeing engaged with the first gear-shifting gear 412. Accordingly, theultra-low speed input gear 42 rotates the first gear-shifting gear 412while rotating as the main gear-shifting output member 221 rotates. Theultra-low speed input gear 42 may transmit the driving power using aplurality of gear teeth. For example, the ultra-low speed input gear 42may be a helical gear. The ultra-low speed input gear 42 may be formedto have a smaller diameter than the first gear-shifting gear 412.Accordingly, deceleration gear shifting, in which the speed becomesslow, may be achieved in a process in which the driving power istransmitted from the ultra-low speed input gear 42 to the firstgear-shifting gear 412.

The ultra-low speed output gear 43 may be connected to the ultra-lowspeed gear-shifting mechanism 41. Accordingly, the ultra-low speedoutput gear 43 may be rotated by the driving power transmitted throughthe ultra-low speed gear-shifting mechanism 41. The ultra-low speedoutput gear 43 may be connected to the second gear-shifting gear 413.The ultra-low speed output gear 43 may be connected to the secondgear-shifting gear 413 by being engaged with the second gear-shiftinggear 413. Accordingly, the ultra-low speed output gear 43 may rotate asthe second gear-shifting gear 413 rotates. The ultra-low speed outputgear 43 may receive the driving power using a plurality of gear teeth.For example, the ultra-low speed output gear 43 may be a helical gear.The ultra-low speed output gear 43 may be formed to have a greaterdiameter than the second gear-shifting gear 413. Accordingly,deceleration gear shifting, in which the speed becomes slow, may beachieved in a process in which the driving power is transmitted from thesecond gear-shifting gear 413 to the ultra-low speed output gear 43.Accordingly, since the deceleration gear shifting is achieved whiletransmitting the driving power from ultra-low speed input gear 42 to thefirst gear-shifting gear 412, and additional deceleration gear shiftingis achieved while transmitting the driving power from the secondgear-shifting gear 413 to the ultra-low speed output gear 43, theultra-low speed gear-shifting part 4 may perform the ultra-low speedgear shifting. The ultra-low speed output gear 43 may be connected tothe second gear-shifting part 120. The ultra-low speed output gear 43may output the driving power in which the ultra-low speed gear shiftingis performed to the second gear-shifting part 120 through the ultra-lowspeed sleeve 44.

The ultra-low speed sleeve 44 may be disposed between the maingear-shifting output member 221 and the second gear-shifting part 120.The ultra-low speed sleeve 44 may selectively connect the secondgear-shifting part 120 to the main gear-shifting output mechanism 22 orthe ultra-low speed output gear 43.

For example, when the normal gear shifting is selected, the ultra-lowspeed sleeve 44 may connect the main gear-shifting output member 221 tothe second gear-shifting part 120. Accordingly, the driving power inwhich the first gear shifting is performed may be transmitted from themain gear-shifting part 2 to the second gear-shifting part 120 afterpassing through the main gear-shifting output member 221 and theultra-low speed sleeve 44.

For example, when the ultra-low speed gear shifting is selected, theultra-low speed sleeve 44 may connect the ultra-low speed output gear 43to the second gear-shifting part 120. Accordingly, the driving power inwhich the first gear shifting is performed may be transmitted from themain gear-shifting part 2 to the second gear-shifting part 120 afterpassing through the main gear-shifting output member 221, the ultra-lowspeed input gear 42, the first gear-shifting gear 412, the couplingmember 414, the second gear-shifting gear 413, the ultra-low speedoutput gear 43, and the ultra-low speed sleeve 44. The ultra-low speedsleeve 44 may be a synchronizer sleeve.

Referring to FIGS. 23 to 25, the second gear-shifting part 120 mayinclude the sub gear-shifting part 3.

The sub gear-shifting part 3 performs second gear shifting to adjust thespeed of the agricultural working automobile. The sub gear-shifting part3 may include the sub gear-shifting drive mechanism 33.

The sub gear-shifting drive mechanism 33 performs the gear shiftingusing the driving power transmitted through one power transmission pathselected between the first power transmission path TP1 and the secondpower transmission path TP2. The sub gear-shifting drive mechanism 33may be connected to the first gear-shifting part 110 through each of thefirst power transmission path TP1 and the second power transmission pathTP2. In this case, the first gear-shifting part 110 may output thedriving power in which the first gear shifting is performed to the subgear-shifting part 3 through the first power transmission path TP1 andthe second power transmission path TP2. The sub gear-shifting drivemechanism 33 may perform the second gear shifting using the drivingpower transmitted through one power transmission path selected betweenthe first power transmission path TP1 and the second power transmissionpath TP2. The first power transmission path TP1 is a path through whichthe driving power is transmitted from the main gear-shifting part 2 tothe sub gear-shifting part 3 after passing through the ultra-low speedgear-shifting part 4. The second power transmission path TP2 is a paththrough which the driving power is transmitted directly from the maingear-shifting part 2 to the sub gear-shifting part 3 without passingthrough the ultra-low speed gear-shifting part 4. That is, thetransmission apparatus 1 of an agricultural working automobile accordingto the second embodiment of the present invention is implemented so thatthe first gear-shifting part 110 and the sub gear-shifting part 3 areconnected to each other through the first power transmission path TP1passing through the ultra-low speed gear-shifting part 4 and the secondpower transmission path TP2 without passing through the ultra-low speedgear-shifting part 4.

Accordingly, the transmission apparatus 1 of an agricultural workingautomobile according to the second embodiment of the present inventionis implemented to include the second power transmission path TP2 so thata part of a speed region is prevented from being unnecessarilyoverlapped and to prevent the ultra-low speed gear shifting from beingapplied even when the sub gear-shifting part 3 performs a high speedgear shifting so that an increase in maintenance costs due to a decreasein fuel efficiency may be reduced. Also, the transmission apparatus 1 ofan agricultural working automobile according to the second embodiment ofthe present invention may divide the configuration for transmitting thedriving power to the sub gear-shifting drive mechanism 33 into each ofthe first power transmission path TP1 and the second power transmissionpath TP2, thereby alleviating complexity of the configuration fortransmitting the driving power to the sub gear-shifting drive mechanism33 and improving ease of manufacturing work.

Referring to FIGS. 23 to 25, the sub gear-shifting part 3 may includethe sub gear-shifting input mechanism 31 and the sub gear-shiftingconnection mechanism 32.

The sub gear-shifting input mechanism 31 may be connected to theultra-low speed gear-shifting part 4. Accordingly, the sub gear-shiftinginput mechanism 31 may implement the first power transmission path whichreceives the driving power from the ultra-low speed gear-shifting part4. The sub gear-shifting input mechanism 31 may receive the drivingpower, in which the normal gear shifting or the ultra-low speed gearshifting is performed, from the ultra-low speed gear-shifting part 4.The sub gear-shifting input mechanism 31 may transmit the driving powertransmitted from the ultra-low speed gear-shifting part 4 to the subgear-shifting drive mechanism 33.

The sub gear-shifting input mechanism 31 may be connected to theultra-low speed output gear 43. The ultra-low speed output gear 43 maybe idly coupled to the sub gear-shifting input mechanism 31. Theultra-low speed output gear 43 may output the driving power in which theultra-low speed gear shifting is performed to the sub gear-shiftinginput mechanism 31 through the ultra-low speed sleeve 44. The ultra-lowspeed sleeve 44 may be disposed between the main gear-shifting outputmember 221 and the sub gear-shifting input mechanism 31. The ultra-lowspeed sleeve 44 may selectively connect the sub gear-shifting inputmechanism 31 to the main gear-shifting output mechanism 22 or theultra-low speed output gear 43.

For example, when the normal gear shifting is selected, the ultra-lowspeed sleeve 44 may connect the main gear-shifting output member 221 tothe sub gear-shifting input mechanism 31. Accordingly, the driving powerin which the first gear shifting is performed may be transmitted fromthe main gear-shifting part 2 to the sub gear-shifting part 3 afterpassing through the main gear-shifting output member 221, ultra-lowspeed sleeve 44, and the sub gear-shifting input mechanism 31.

For example, when the ultra-low speed gear shifting is selected, theultra-low speed sleeve 44 may connect the ultra-low speed output gear 43to the sub gear-shifting input mechanism 31. Accordingly, the drivingpower in which the first gear shifting is performed may be transmittedfrom the main gear-shifting part 2 to the sub gear-shifting part 3 afterpassing through the main gear-shifting output member 221, the ultra-lowspeed input gear 42, the first gear-shifting gear 412, the couplingmember 414, the second gear-shifting gear 413, the ultra-low speedoutput gear 43, the ultra-low speed sleeve 44, and the sub gear-shiftinginput mechanism 31.

The sub gear-shifting input mechanism 31 may include the subgear-shifting input gear 311 and the sub gear-shifting input member 312.

The sub gear-shifting input gear 311 may be connected to the subgear-shifting input member 312. Accordingly, the sub gear-shifting inputgear 311 may rotate as the sub gear-shifting input member 312 rotates.The sub gear-shifting input gear 311 receives the driving power from thesub gear-shifting input member 312 and may transmit the received driveto the sub gear-shifting drive mechanism 33. The sub gear-shifting inputgear 311 may be connected to the sub gear-shifting input member 312 bybeing coupled to the sub gear-shifting input member 312.

The sub gear-shifting input member 312 may be connected to the ultra-lowspeed gear-shifting part 4. Accordingly, the sub gear-shifting inputmember 312 may receive the driving power from the ultra-low speedgear-shifting part 4. The sub gear-shifting input member 312 may beconnected to the ultra-low speed sleeve 44. The sub gear-shifting inputgear 311 may be coupled to the sub gear-shifting input member 312.Accordingly, when the normal gear shifting is selected, the drivingpower in which the first gear shifting is performed may be transmittedto the sub gear-shifting drive mechanism 33 after passing through themain gear-shifting output member 221, the ultra-low speed sleeve 44, thesub gear-shifting input member 312, and the sub gear-shifting input gear311. When the ultra-low speed gear shifting is selected, the drivingpower in which the first gear shifting is performed may be transmittedto the sub gear-shifting drive mechanism 33 after passing through themain gear-shifting output member 221, the ultra-low speed input gear 42,the first gear-shifting gear 412, the coupling member 414, the secondgear-shifting gear 413, the ultra-low speed output gear 43, theultra-low speed sleeve 44, the sub gear-shifting input member 312, andthe sub gear-shifting input gear 311.

The sub gear-shifting input member 312 may be disposed parallel to thefirst axis direction (the X axis direction). The sub gear-shifting inputmember 312 may function as a rotation shaft in the sub gear-shiftinginput mechanism 31. For example, the sub gear-shifting input member 312may be a shaft. The sub gear-shifting input member 312 may function asone of the power transmission paths through which the sub gear-shiftingpart 3 receives the driving power. The sub gear-shifting input member312 and the main gear-shifting output member 221 may be disposed on thesame line.

The sub gear-shifting connection mechanism 32 may be connected to themain gear-shifting part 2. Accordingly, the sub gear-shifting connectionmechanism 32 may implement the second power transmission path throughwhich the driving power in which the first gear shifting is performed isdirectly transmitted from the main gear-shifting part 2. The subgear-shifting connection mechanism 32 may be connected to the maingear-shifting part 2 so that the second power transmission path isimplemented, by being connected to the main gear-shifting drivemechanism 21. The sub gear-shifting connection mechanism 32 may beconnected to the sub gear-shifting drive mechanism 33. Accordingly, thesub gear-shifting connection mechanism 32 may transmit the driving powertransmitted through the second power transmission path to the subgear-shifting drive mechanism 33.

Accordingly, the sub gear-shifting part 3 may include the first powertransmission path which receives the driving power from the maingear-shifting part 2 after passing through the ultra-low speedgear-shifting part 4 through the sub gear-shifting input mechanism 31,and the second power transmission path which directly receives thedriving power from the main gear-shifting part 2 without passing throughthe ultra-low speed gear-shifting part 4 through the sub gear-shiftingconnection mechanism 32. Meanwhile, the main gear-shifting part 2 mayinclude a first power output path which outputs the driving powerthrough the main gear-shifting output member 221 and a second poweroutput path which outputs the driving power through the subgear-shifting connection mechanism 32.

Accordingly, the transmission apparatus 1 of an agricultural workingautomobile according to the second embodiment of the present inventionmay prevent a part of the speed region from being unnecessarilyoverlapped and reduce an increase in maintenance costs due to a decreasein fuel efficiency by being implemented to prevent the ultra-low speedgear-shifting from being applied even when the sub gear-shifting part 3performs high speed gear shifting. Also, in the transmission apparatus 1of an agricultural working automobile according to the second embodimentof the present invention, the sub gear-shifting input mechanism 31 andthe sub gear-shifting connection mechanism 32 may share theconfiguration for transmitting the driving power to the subgear-shifting drive mechanism 33, thereby implementing the configurationof the sub gear-shifting input mechanism 31 in a simple manner Thus, thetransmission apparatus 1 of an agricultural working automobile accordingto the second embodiment of the present invention may alleviatecomplexity of the configuration for the sub gear-shifting inputmechanism 31 and also improve ease of manufacturing work.

The sub gear-shifting connection mechanism 32 may be disposed to bepositioned between the main gear-shifting drive mechanism 21 and the subgear-shifting drive mechanism 33. One side of the sub gear-shiftingconnection mechanism 32 may be connected to the main gear-shifting drivemechanism 21. The other side of the sub gear-shifting connectionmechanism 32 may be connected to the sub gear-shifting drive mechanism33. The sub gear-shifting connection mechanism 32 may traverse theultra-low speed gear-shifting part 4 to be coupled to each of the maingear-shifting drive mechanism 21 and the sub gear-shifting drivemechanism 33. In this case, a connection hole 411 may be formed in theultra-low speed gear-shifting mechanism 41. The connection hole 411 maybe formed to pass through the coupling member 414 of the ultra-low speedgear-shifting mechanism 41. The sub gear-shifting connection mechanism32 is positioned in the ultra-low speed gear-shifting mechanism 41through the connection hole 411 to connect the main gear-shifting drivemechanism 21 to the sub gear-shifting drive mechanism 33. Accordingly,the transmission apparatus 1 of an agricultural working automobileaccording to the second embodiment of the present invention may reducethe length of the sub gear-shifting connection mechanism 32 on the basisof the first axis direction (the X axis direction), thereby not onlyimproving drive transmission performance to the sub gear-shiftingconnection mechanism 32 but also reducing manufacturing costs for thesub gear-shifting connection mechanism 32. Further, in the transmissionapparatus 1 of an agricultural working automobile according to thesecond embodiment of the present invention, the sub gear-shiftingconnection mechanism 32 may connect the sub gear-shifting drive gear 331to the main gear-shifting drive gear 211 in a direct connection manner,thereby implementing the configuration for connecting the subgear-shifting drive gear 331 to the main gear-shifting drive gear 211 ina simple manner. The ultra-low speed gear-shifting mechanism 41 may beidly coupled to the sub gear-shifting connection mechanism 32 installedin the connection hole 411. The coupling member 414 of the ultra-lowspeed gear-shifting mechanism 41 may be idly coupled to the subgear-shifting connection mechanism 32. A bearing (not shown) may beinstalled between the coupling member 414 and the sub gear-shiftingconnection mechanism 32.

The sub gear-shifting connection mechanism 32 may be disposed on thesame line as the main gear-shifting drive mechanism 20. Accordingly, thetransmission apparatus 1 of an agricultural working automobile accordingto the second embodiment of the present invention may improve ease ofmanufacturing work by improving ease of disposition for the maingear-shifting drive mechanism 21 and the sub gear-shifting drivemechanism 33. The sub gear-shifting connection mechanism 32 may be ashaft.

The sub gear-shifting drive mechanism 33 will be described in moredetail with reference to FIGS. 23 to 27 as below.

Referring to FIGS. 24 and 25, the sub gear-shifting drive mechanism 33may be connected to each of the sub gear-shifting input mechanism 31 andthe sub gear-shifting connection mechanism 32. The sub gear-shiftingdrive mechanism 33 may perform the second gear shifting using onedriving power selected from the driving power transmitted from the subgear-shifting input mechanism 31 and the driving power transmitted fromthe sub gear-shifting connection mechanism 32. That is, the subgear-shifting drive mechanism 33 may perform the second gear shiftingusing one driving power selected from the driving power transmittedthrough the first power transmission path and the driving powertransmitted through the second power transmission path. The drivingpower transmitted through the first power transmission path istransmitted from the first main gear-shifting output mechanism 22 afterpassing through the ultra-low speed gear-shifting part 4. In this case,the driving power transmitted through the first power transmission pathis a driving power in which the normal gear shifting or the ultra-lowspeed gear shifting is performed after the first gear shifting isperformed. The driving power transmitted through the second powertransmission path is directly transmitted from the first maingear-shifting drive mechanism 21 without passing through the ultra-lowspeed gear-shifting part 4. In this case, the driving power transmittedthrough the second power transmission path is a driving power in whichonly the first gear shifting is performed. The sub gear-shifting drivemechanism 33 may perform the second gear shifting using one drivingpower selected by gear-shifting operation of the operator.

Referring to FIGS. 25 to 27, when the sub gear-shifting part 3 performsthe second gear shifting in two stages, the sub gear-shifting drivemechanism 33 may include the first sub gear-shifting drive gear 331 a,the second sub gear-shifting drive gear 331 b, and the first subgear-shifting sleeve 332 a.

The first sub gear-shifting drive gear 331 a may be idly coupled to thesub gear-shifting output mechanism 30. A bearing (not shown) may beinstalled between the first sub gear-shifting drive gear 331 a and thesub gear-shifting output mechanism 30. The first sub gear-shifting drivegear 331 a may be rotated by the driving power provided from the subgear-shifting input mechanism 31. In this case, the first subgear-shifting drive gear 331 a may include a first input gear 4311 a forbeing connected to the sub gear-shifting input mechanism 31 and a firstoutput gear 4312 a for being connected to the first sub gear-shiftingsleeve 332 a. The first input gear 4311 a may be engaged with the subgear-shifting input gear 311. Accordingly, the first sub gear-shiftingdrive gear 331 a may rotate as the sub gear-shifting input gear 311rotates. That is, the first sub gear-shifting drive gear 331 a may berotated by the driving power transmitted through the first powertransmission path. In this case, when the first output gear 4312 a isconnected to the first sub gear-shifting sleeve 332 a, the first subgear-shifting drive gear 331 a is rotated by the driving powertransmitted through the first power transmission path in order to rotatethe first sub gear-shifting sleeve 332 a and the sub gear-shiftingoutput mechanism 30.

The second sub gear-shifting drive gear 331 b may be disposed to bespaced apart from the first sub gear-shifting drive gear 331 a in thefirst axis direction (the X axis direction). The first sub gear-shiftingsleeve 332 a may be disposed between the second sub gear-shifting drivegear 331 b and the first sub gear-shifting drive gear 331 a. The secondsub gear-shifting drive gear 331 b may be disposed between the first subgear-shifting sleeve 332 a and the ultra-low speed gear-shifting part 4.The second sub gear-shifting drive gear 331 b may be rotated by thedriving power provided from the sub gear-shifting connection mechanism32. That is, the second sub gear-shifting drive gear 331 b may berotated by the driving power transmitted through the second powertransmission path. One side of the sub gear-shifting connectionmechanism 32 may be coupled to the second main gear-shifting drive gear211 b and the other side of the sub gear-shifting connection mechanism32 may be coupled to the second sub gear-shifting drive gear 331 b.Among the main gear-shifting drive gears 211 and the sub gear-shiftingdrive gears 331, the second main gear-shifting drive gear 211 b and thesecond sub gear-shifting drive gear 331 b are disposed to be spacedapart from each other by the shortest distance on the basis of the firstaxis direction (the X axis direction). One side of the sub gear-shiftingconnection mechanism 32 may be coupled to the second drive output gear2112 b of the second main gear-shifting drive gear 211 b.

The second sub gear-shifting drive gear 331 b may include a secondoutput gear for being connected to the first sub gear-shifting sleeve332 a. In this case, when the second output gear is connected to thefirst sub gear-shifting sleeve 332 a, the second sub gear-shifting drivegear 331 b is rotated by the driving power transmitted through thesecond power transmission path in order to rotate the first subgear-shifting sleeve 332 a.

The first sub gear-shifting sleeve 332 a may be coupled to the subgear-shifting output mechanism 30 so as to be positioned between thefirst sub gear-shifting drive gear 331 a and the second subgear-shifting drive gear 331 b. The first sub gear-shifting sleeve 332 amay be coupled to the sub gear-shifting output mechanism 30 to bemovable in the first axis direction (the X axis direction). Accordingly,the first sub gear-shifting sleeve 332 a may be selectively connected tothe first sub gear-shifting drive gear 331 a or the second subgear-shifting drive gear 331 b to perform the second gear shifting. Inthis case, the first sub gear-shifting sleeve 332 a may be selectivelyconnected to the first sub gear-shifting drive gear 331 a or the secondsub gear-shifting drive gear 331 b by the gear-shifting operation of theoperator while moving along the first axis direction (the X axisdirection).

As shown in FIG. 26, when the first sub gear-shifting sleeve 332 a isconnected to the first sub gear-shifting drive gear 331 a, the first subgear-shifting sleeve 332 a may receive the driving power transmittedthrough the first power transmission path through the sub gear-shiftinginput mechanism 31. Accordingly, the sub gear-shifting drive mechanism33 may perform the second gear shifting using the sub gear-shiftinginput mechanism 31, the first sub gear-shifting drive gear 331 a, andthe first sub gear-shifting sleeve 332 a and output the driving power inwhich the second gear shifting is performed through the subgear-shifting output mechanism 30. When the first sub gear-shiftingsleeve 332 a is connected to the first sub gear-shifting drive gear 331a, the first sub gear-shifting sleeve 332 a may receive the drivingpower through the first power transmission path for all firstgear-shifting stages performable by the main gear-shifting part 2 andall gear-shifting stages performable by the ultra-low speedgear-shifting part 4.

In this case, when normal gear shifting is selected in the ultra-lowspeed gear-shifting part 4, the driving power in which the first gearshifting is performed is sequentially transmitted through the ultra-lowspeed sleeve 44 and the sub gear-shifting input member 312 to performthe normal gear shifting and may be transmitted to the first subgear-shifting sleeve 332 a. In this case, the driving power may betransmitted along a solid-line arrow shown in the ultra-low speedgear-shifting part 4 of FIG. 26. When an ultra-low speed gear shiftingis selected in the ultra-low speed gear-shifting part 4, the drivingpower in which the first gear shifting is performed is sequentiallytransmitted through the ultra-low speed input gear 42, the ultra-lowspeed gear-shifting mechanism 41, the ultra-low speed output gear 43,the ultra-low speed sleeve 44, and the sub gear-shifting input member312 to perform the ultra-low speed gear shifting and may be transmittedto the first sub gear-shifting sleeve 332 a. In this case, the drivingpower may be transmitted along dot dash-line arrows shown in theultra-low speed gear-shifting part 4 of FIG. 26.

As shown in FIG. 27, when the first sub gear-shifting sleeve 332 a isconnected to the second sub gear-shifting drive gear 331 b, the firstsub gear-shifting sleeve 332 a may receive the driving power transmittedthrough the second power transmission path through the sub gear-shiftingconnection mechanism 32. Accordingly, the sub gear-shifting drivemechanism 33 may perform the second gear shifting using the subgear-shifting connection mechanism 32, the second sub gear-shiftingdrive gear 331 b, and the first sub gear-shifting sleeve 332 a andoutput the driving power in which the second gear shifting is performedto the sub gear-shifting output mechanism 30. When the first subgear-shifting sleeve 332 a is connected to the second sub gear-shiftingdrive gear 331 b, the first sub gear-shifting sleeve 332 a may receivethe driving power in which the first gear shifting is performed throughthe second power transmission path for all first gear-shifting stagesperformable by the main gear-shifting part 2. In this case, the drivingpower in which the first gear shifting is performed may be directlytransmitted to the sub gear-shifting part 3 without passing through theultra-low speed gear-shifting part 4.

Referring to FIGS. 29 and 30, the transmission apparatus 1 of anagricultural working automobile according to the second embodiment ofthe present invention may be implemented to include the subgear-shifting part 3 according to the above-described modifiedembodiment of the present invention. In this case, the sub gear-shiftingpart 3 may include the third sub gear-shifting drive gear 331 c, thesecond sub gear-shifting sleeve 332 b, the connection shaft 333, thefirst connection gear 334, and the second connection gear 335. This issubstantially the same as that described in the sub gear-shifting part 3according to the above-described modified embodiment of the presentinvention, and thus a detailed description thereof will be omitted.

Referring to FIGS. 31 and 32, in the transmission apparatus 1 of anagricultural working automobile according to the second embodiment ofthe present invention, a main gear-shifting through hole 221 a may beformed in the main gear-shifting output member 221. The maingear-shifting through hole 221 a may be formed to pass through the maingear-shifting output member 221. A sub gear-shifting through hole 312 amay be formed in the sub gear-shifting input member 312. The subgear-shifting through hole 312 a may be formed to pass through the subgear-shifting input member 312.

Accordingly, the power transmission shaft 200 may be installed insidethe main gear-shifting output member 221 and inside the subgear-shifting input member 312. The power transmission shaft 200 isinstalled to traverse the inside of the main gear-shifting output member221 and the inside of the sub gear-shifting input member 312 through themain gear-shifting through hole 221 a and the sub gear-shifting throughhole 312 a to transmit a predetermined drive. Accordingly, thetransmission apparatus 1 of a working automobile according to the secondembodiment of the present invention may contribute to further improvingutilization of a space for installing and disposing various devices onthe agricultural working automobile.

Referring to FIG. 33, in the transmission apparatus 1 of an agriculturalworking automobile according to the second embodiment of the presentinvention, an ultra-low speed gear-shifting part 4 according a modifiedembodiment of the present invention may be implemented as describedbelow.

The ultra-low speed gear-shifting mechanism 41 may be disposed to bepositioned at a position spaced apart from each of the maingear-shifting output member 221 and the sub gear-shifting connectionmechanism 32. Accordingly, the ultra-low speed gear-shifting mechanism41 may be disposed at a position spaced apart from a space between themain gear-shifting drive mechanism 21 and the sub gear-shifting drivemechanism 33 so as to avoid the sub gear-shifting connection mechanism32. Accordingly, the sub gear-shifting connection mechanism 32 mayconnect the main gear-shifting drive mechanism 21 to the subgear-shifting drive mechanism 33 without being interfered with by theultra-low speed gear-shifting mechanism 41 even without the connectionhole 411. Thus, the transmission apparatus 1 of an agricultural workingautomobile according to the second embodiment of the present inventionmay simply implement a configuration for connecting the maingear-shifting drive mechanism 21 to the sub gear-shifting drivemechanism 33 in a direct connection manner.

The ultra-low speed gear-shifting mechanism 41 may be disposed so thatthe coupling member 414 is positioned at a position spaced apart fromeach of the main gear-shifting output member 221 and the subgear-shifting connection mechanism 32. For example, the maingear-shifting output member 221 may be disposed to be positioned betweenthe coupling member 414 and the sub gear-shifting connection mechanism32. The coupling member 414, the main gear-shifting output member 221,and the sub gear-shifting connection mechanism 32 may be disposedparallel to each other. In this case, the sub gear-shifting input member312 may be disposed to be positioned between the coupling member 414 andthe sub gear-shifting connection mechanism 32. The coupling member 414,the main gear-shifting output member 221, the sub gear-shiftingconnection mechanism 32, and the sub gear-shifting input member 312 maybe disposed parallel to each other. In this case, the main gear-shiftingoutput member 221 and the sub gear-shifting input member 312 may bedisposed to be positioned on the same line.

The ultra-low speed gear-shifting mechanism 41 may be implemented sothat the ultra-low speed input gear 42 is disposed between the firstgear-shifting gear 412 and the sub gear-shifting connection mechanism32. The ultra-low speed gear-shifting mechanism 41 may be implemented sothat the ultra-low speed output gear 43 is disposed between the secondgear-shifting gear 413 and the sub gear-shifting connection mechanism32.

Referring to FIG. 34, an ultra-low speed gear-shifting part 4 accordingto another modified embodiment of the present invention may beimplemented as described below.

The ultra-low speed gear-shifting part 4 may be connected to each of themain gear-shifting drive mechanism 21 and the sub gear-shiftingconnection mechanism 32. The ultra-low speed input gear 42, theultra-low speed output gear 43, and the ultra-low speed sleeve 44 may bedisposed between the main gear-shifting drive mechanism 21 and the subgear-shifting drive mechanism 33 on the basis of the first axisdirection (the X axis direction). The ultra-low speed gear-shiftingmechanism 41 may be disposed between the main gear-shifting outputmechanism 22 and the sub gear-shifting input mechanism 31 on the basisof the first axis direction (the X axis direction).

The sub gear-shifting connection mechanism 32 may be connected to theultra-low speed gear-shifting part 4 to implement the first powertransmission path. In this case, the main gear-shifting drive mechanism21 may include a main gear-shifting drive member 213. The ultra-lowspeed input gear 42 may be connected to the main gear-shifting drivemechanism 21 by being coupled to the main gear-shifting drive member213. The main gear-shifting drive member 213 may function as a rotationshaft of the ultra-low speed input gear 42. For example, the maingear-shifting drive member 213 may be a shaft. The ultra-low speedoutput gear 43 may be idly coupled to the sub gear-shifting connectionmechanism 32. The ultra-low speed sleeve 44 may selectively connect thesub gear-shifting connection mechanism 32 to the main gear-shiftingdrive member 213 or the ultra-low speed output gear 43.

The sub gear-shifting input mechanism 31 may be directly connected tothe main gear-shifting output mechanism 22 to implement the second powertransmission path. When the ultra-low speed gear-shifting mechanism 41is disposed between the main gear-shifting output mechanism 22 and thesub gear-shifting input mechanism 31 on the basis of the first axisdirection (the X axis direction), the sub gear-shifting input member 312is positioned in the ultra-low speed gear-shifting mechanism 41 throughthe connection hole 411 formed in the ultra-low speed gear-shiftingmechanism 41 to directly connect the main gear-shifting output member221 to the sub gear-shifting input gear 311. Although not shown in thedrawings, the ultra-low speed gear-shifting mechanism 41 may also bedisposed to be positioned at a position spaced apart from each of thesub gear-shifting input member 312 and the sub gear-shifting connectionmechanism 32. In this case, the ultra-low speed gear-shifting mechanism31 may be disposed at a positon spaced apart from a space between themain gear-shifting output mechanism 22 and the sub gear-shifting inputmechanism 31 so as to avoid the sub gear-shifting input member 312.Accordingly, the sub gear-shifting input member 312 may connect the maingear-shifting output mechanism 22 to the sub gear-shifting input gear311 without being interfered with by the ultra-low speed gear-shiftingmechanism 41 even without the connection hole 411.

When an ultra-low speed gear-shifting part 3 according to anothermodified embodiment of the present invention is applied, the maingear-shifting part 2 may be implemented so that the fourth maingear-shifting drive gear 211 d is connected to the ultra-low speedgear-shifting part 4, and the fourth main gear-shifting output gear 222d is directly connected to the sub gear-shifting input mechanism 31through the main gear-shifting output member 221. In this case, the maingear-shifting part 2 may correspond to an embodiment in which the fourthmain gear-shifting drive gear 211 d is implemented as a fourth speedstage, the third main gear-shifting drive gear 211 c is implemented as athird speed stage, the second main gear-shifting drive gear 211 b isimplemented as a second speed stage, and the first main gear-shiftingdrive gear 211 a is implemented as a first speed stage, in order fromthe highest speed to the lowest speed.

Referring to FIGS. 35 and 36, a transmission apparatus 1 of anagricultural working automobile according to a modified secondembodiment of the present invention may include the first gear-shiftingpart 110 and the second gear-shifting part 120. Since the firstgear-shifting part 110 and the second gear-shifting part 120 aresubstantially the same as those described in the transmission apparatus1 of an agricultural working automobile according to the secondembodiment of the present invention, the following description willfocus on parts with differences.

The sub gear-shifting connection mechanism 32 may be connected to theultra-low speed gear-shifting part 4. Accordingly, the sub gear-shiftingconnection mechanism 32 may implement the first power transmission pathwhich receives the driving power after passing through the ultra-lowspeed gear-shifting part 4. One side of the sub gear-shifting connectionmechanism 32 may be connected to the ultra-low speed gear-shifting part3 and the other side of the sub gear-shifting connection mechanism 32may be connected to the sub gear-shifting drive mechanism 33.Accordingly, when the driving power transmitted through the first powertransmission path is selected by the gear-shifting operation, the subgear-shifting drive mechanism 33 may perform the second gear shiftingusing the driving power transmitted from the main gear-shifting outputmechanism 22 after passing through the ultra-low speed gear-shiftingpart 4 through the sub gear-shifting connection mechanism 32. In thiscase, the ultra-low speed sleeve 44 may selectively connect the subgear-shifting connection mechanism 32 to the main gear-shifting outputmechanism 22 or the ultra-low speed output gear 43. One side of the subgear-shifting drive mechanism 33 may be connected to the ultra-low speedsleeve 44. The other side of the sub gear-shifting drive mechanism 33may be connected to the second sub gear-shifting drive gear 331 b.

The sub gear-shifting input mechanism 31 may be directly connected tothe main gear-shifting drive mechanism 21. Accordingly, the subgear-shifting input mechanism 31 may implement the second powertransmission path which receives the driving power without passingthrough the ultra-low speed gear-shifting part 4. The sub gear-shiftinginput mechanism 31 may be connected to each of the main gear-shiftingdrive mechanism 21 and the sub gear-shifting drive mechanism 33.Accordingly, when the driving power transmitted through the second powertransmission path is selected by the gear-shifting operation, the subgear-shifting drive mechanism 33 may perform the second gear shiftingusing the driving power directly transmitted from the main gear-shiftingdrive mechanism 21 through the sub gear-shifting input mechanism 31.When the sub gear-shifting input mechanism 31 includes the subgear-shifting input member 312 and the sub gear-shifting input gear 311,one side of the sub gear-shifting input member 312 may be connected tothe main gear-shifting drive mechanism 21. The one side of the subgear-shifting input member 312 may be connected to the second maingear-shifting drive gear 211 b. The other side of the sub gear-shiftinginput member 312 may be connected to the sub gear-shifting input gear311. The sub gear-shifting input gear 311 may be connected to the firstsub gear-shifting drive gear 331 a.

The sub gear-shifting input member 312 is positioned in the ultra-lowspeed gear-shifting mechanism 41 through the connection hole 411 formedin the ultra-low speed gear-shifting mechanism 41 to connect the maingear-shifting drive mechanism 21 to the sub gear-shifting input gear311. In this case, the ultra-low speed gear-shifting mechanism 41 may bedisposed to be positioned between the main gear-shifting part 2 and thesub gear-shifting part 3 on the basis of the first axis direction (the Xaxis direction). The sub gear-shifting input member 312 traverses theultra-low speed gear-shifting mechanism 41 through the connection hole411 to be coupled to each of the main gear-shifting drive mechanism 21and the sub gear-shifting drive mechanism 33.

Referring to FIGS. 37 and 38, a transmission apparatus 1 of anagricultural working automobile according to a modified secondembodiment of the present invention may be implemented to include thesub gear-shifting part 3 according to the above-described modifiedembodiment of the present invention. In this case, the sub gear-shiftingpart 3 may include the third sub gear-shifting drive gear 331 c, thesecond sub gear-shifting sleeve 332 b, the connection shaft 433, thefirst connection gear 434, and the second connection gear 435. This issubstantially the same as that described in the sub gear-shifting part 3according to the above-described modified embodiment of the presentinvention, and thus a detailed description thereof will be omitted.

Referring to FIG. 39, the transmission apparatus 1 of an agriculturalworking automobile according to the modified second embodiment of thepresent invention may be implemented to include the ultra-low speedgear-shifting part 4 according to the above-described modifiedembodiment of the present invention.

The ultra-low speed gear-shifting mechanism 41 may be disposed to bepositioned at a position spaced apart from each of the maingear-shifting output member 221 and the sub gear-shifting input member312. Accordingly, the ultra-low speed gear-shifting mechanism 41 may bedisposed at a position spaced apart from a space between the maingear-shifting drive mechanism 21 and the sub gear-shifting drivemechanism 33 to avoid the sub gear-shifting input member 312.Accordingly, the sub gear-shifting input member 312 may connect the maingear-shifting drive mechanism 21 to the sub gear-shifting input gear 311without being interfered with by the ultra-low speed gear-shiftingmechanism 41 even without the connection hole 411. Thus, thetransmission apparatus 1 of an agricultural working automobile accordingto the modified second embodiment of the present invention may simplyimplement a configuration for connecting the main gear-shifting drivemechanism 21 to the sub gear-shifting input gear 311 in a directconnection manner.

The ultra-low speed gear-shifting mechanism 41 may be disposed so thatthe coupling member 414 is positioned at a position spaced apart fromeach of the main gear-shifting output member 221 and the subgear-shifting input member 312. For example, the main gear-shiftingoutput member 221 may be disposed to be positioned between the couplingmember 414 and the sub gear-shifting input member 312. The couplingmember 414, the main gear-shifting output member 221, and the subgear-shifting input member 312 may be disposed parallel to each other.In this case, the sub gear-shifting connection mechanism 32 may bedisposed to be positioned between the coupling member 414 and the subgear-shifting input member 312. The coupling member 414, the maingear-shifting output member 221, the sub gear-shifting input member 312,and the sub gear-shifting connection mechanism 32 may be disposedparallel to each other. In this case, the main gear-shifting outputmember 221 and the sub gear-shifting connection mechanism 32 may bedisposed to be positioned on the same line.

The ultra-low speed gear-shifting mechanism 41 may be implemented sothat the ultra-low speed input gear 42 is disposed between the firstgear-shifting gear 412 and the sub gear-shifting input member 312. Theultra-low speed gear-shifting mechanism 41 may be implemented so thatthe ultra-low speed output gear 43 is disposed between the secondgear-shifting gear 413 and the sub gear-shifting input member 312.

Referring to FIG. 40, the transmission apparatus 1 of an agriculturalworking automobile according to the modified second embodiment of thepresent invention may be implemented to include the ultra-low speedgear-shifting part 4 according to the above-described another modifiedembodiment of the present invention.

The ultra-low speed gear-shifting part 4 may be connected to each of themain gear-shifting drive mechanism 21 and the sub gear-shifting inputmechanism 31. The ultra-low speed input gear 42, the ultra-low speedoutput gear 43, and the ultra-low speed sleeve 44 may be disposedbetween the main gear-shifting drive mechanism 21 and the subgear-shifting input mechanism 31 on the basis of the first axisdirection (the X axis direction). The ultra-low speed gear-shiftingmechanism 41 may be disposed between the main gear-shifting outputmechanism 22 and the sub gear-shifting drive mechanism 33 on the basisof the first axis direction (the X axis direction).

The sub gear-shifting input mechanism 31 may be connected to theultra-low speed gear-shifting part 4 to implement the first powertransmission path. In this case, the ultra-low speed input gear 42 maybe connected to the main gear-shifting drive mechanism 21 by beingcoupled to the main gear-shifting drive member 213. The ultra-low speedoutput gear 43 may be idly coupled to sub gear-shifting input member312. The ultra-low speed sleeve 44 may selectively connect the subgear-shifting input member 312 to the main gear-shifting drive member213 or the ultra-low speed output gear 43.

The sub gear-shifting connection mechanism 32 may be directly connectedto the main gear-shifting output mechanism 22 to implement the secondpower transmission path. When the ultra-low speed gear-shiftingmechanism 41 is disposed between the main gear-shifting output mechanism22 and the sub gear-shifting drive mechanism 33 on the basis of thefirst axis direction (the X axis direction), the sub gear-shiftingconnection mechanism 32 is positioned in the ultra-low speedgear-shifting mechanism 41 through the connection hole 411 formed in theultra-low speed gear-shifting mechanism 41 to directly connect the maingear-shifting output member 221 to the sub gear-shifting drive mechanism33. Although not shown in the drawings, the ultra-low speedgear-shifting mechanism 41 may also be disposed to be positioned at aposition spaced apart from each of the sub gear-shifting input member312 and the sub gear-shifting connection mechanism 32. In this case, theultra-low speed gear-shifting mechanism 41 may be disposed at a positionspaced apart from a space between the main gear-shifting outputmechanism 22 and the sub gear-shifting drive mechanism 33 so as to avoidthe sub gear-shifting connection mechanism 32. Accordingly, the subgear-shifting connection mechanism 32 may connect the main gear-shiftingoutput mechanism 22 to the sub gear-shifting drive mechanism 33 withoutbeing interfered with by the ultra-low speed gear-shifting mechanism 41even without the connection hole 411.

When the ultra-low speed gear-shifting part 4 according to anothermodified embodiment of the present invention is applied, the maingear-shifting part 2 may be implemented so that the fourth maingear-shifting drive gear 211 d is connected to the ultra-low speedgear-shifting part 4, and the fourth main gear-shifting output gear 222d is directly connected to the sub gear-shifting connection mechanism 32through the main gear-shifting output member 221. In this case, the maingear-shifting part 2 may correspond to an embodiment in which the fourthmain gear-shifting drive gear 211 d is implemented as a fourth speedstage, the third main gear-shifting drive gear 211 c is implemented as athird speed stage, the second main gear-shifting drive gear 211 b isimplemented as a second speed stage, and the first main gear-shiftingdrive gear 211 a is implemented as a first speed stage, in order fromthe highest speed to the lowest speed.

While the embodiments of the present invention and their advantages havebeen described in detail with reference to the accompanying drawings, itwill be apparent to those skilled in the art to which the presentinvention belongs that various changes, substitutions and alterationsmay be made herein without departing from the scope of the presentinvention.

The invention claimed is:
 1. A transmission apparatus of an agriculturalworking automobile, comprising: a first gear-shifting part whichperforms gear shifting to adjust a speed of an agricultural workingautomobile; and a second gear-shifting part which performs gear shiftingto adjust the speed of the agricultural working automobile, wherein thefirst gear-shifting part includes a main gear-shifting part whichperforms first gear shifting to adjust the speed of the agriculturalworking automobile, wherein the second gear-shifting part includes a subgear-shifting part which performs second gear shifting on a drivingpower transmitted from the first gear-shifting part, wherein the maingear-shifting part includes a main gear-shifting drive mechanism whichperforms the first gear shifting and a main gear-shifting outputmechanism connected to the sub gear-shifting part, wherein subgear-shifting part includes a sub gear-shifting input mechanismconnected to the main gear-shifting output mechanism, a subgear-shifting connection mechanism connected to the main gear-shiftingpart, and a sub gear-shifting drive mechanism which performs the secondgear shifting, wherein the main gear-shifting output mechanism includesa plurality of main gear-shifting output gears connected to the maingear-shifting drive mechanism, and a main gear-shifting output membercoupled to the main gear-shifting output gears, wherein one side of themain gear-shifting output member is coupled to the main gear-shiftingoutput gears and the other side of the main gear-shifting output memberis coupled to the sub gear-shifting input mechanism to implement thefirst power transmission path, wherein one side of the sub gear-shiftingconnection mechanism is coupled to the main gear-shifting drivemechanism and the other side of the sub gear-shifting connectionmechanism is coupled to the sub gear-shifting drive mechanism toimplement the second power transmission path, wherein the subgear-shifting drive mechanism performs the second gear shifting usingone driving power selected from a driving power transmitted through thefirst power transmission path and a driving power transmitted throughthe second power transmission path, wherein the main gear-shifting drivemechanism includes a main gear-shifting input mechanism and a pluralityof main gear-shifting drive gears, wherein the main gear-shifting inputmechanism is rotated by a driving power provided from an engine of theagricultural working automobile, wherein the main gear-shifting drivegears are idly coupled to the main gear-shifting input mechanism,wherein the sub gear-shifting drive mechanism includes a plurality ofsub gear-shifting drive gears, and wherein one side of the subgear-shifting connection mechanism is coupled to one main gear-shiftingdrive gear of the main gear-shifting drive gears, and the other side ofthe sub gear-shifting connection mechanism is coupled to one subgear-shifting drive gear of the sub gear-shifting drive gears.
 2. Thetransmission apparatus of claim 1, wherein the main gear-shifting drivemechanism performs the first gear shifting on the driving power providedfrom the engine, the main gear-shifting output mechanism is connected tothe main gear-shifting drive mechanism so as to be driven as the maingear-shifting drive mechanism is driven, and the sub gear-shifting drivemechanism is connected to the sub gear-shifting input mechanism.
 3. Thetransmission apparatus of claim 2, wherein the sub gear-shifting partincludes a sub gear-shifting output mechanism configured to output adriving power in which the second gear shifting is performed, and thesub gear-shifting output mechanism, the main gear-shifting inputmechanism, and the sub gear-shifting connection mechanism are positionedon the same line.
 4. The transmission apparatus of claim 1, wherein thesub gear-shifting connection mechanism is coupled to each of the one subgear-shifting drive gear and the one main gear-shifting drive gear,which are spaced apart from each other by the shortest distance, amongthe sub gear-shifting drive gears and the main gear-shifting drivegears.
 5. The transmission apparatus of claim 1, wherein the subgear-shifting input mechanism includes a sub gear-shifting input gearconnected to the main gear-shifting output member, the number of the subgear-shifting input gear is fewer than the number of the subgear-shifting drive gears.
 6. The transmission apparatus of claim 1,wherein the sub gear-shifting connection mechanism connects the one maingear-shifting drive gear to the one sub gear-shifting drive gear in adirect connection manner.
 7. The transmission apparatus of claim 1,wherein the sub gear-shifting connection mechanism connects the one maingear-shifting drive gear, which corresponds to the gear-shifting stagehaving the highest frequency of use in the main gear-shifting part, tothe one sub gear-shifting drive gear, which corresponds to thegear-shifting stage having the highest frequency of use in the subgear-shifting part, in a direct connection manner.
 8. The transmissionapparatus of claim 1, wherein the sub gear-shifting connection mechanismis a shaft.
 9. The transmission apparatus of claim 1, wherein, the subgear-shifting drive mechanism includes a first sub gear-shifting sleeve,the first sub gear-shifting sleeve is disposed between a first subgear-shifting drive gear of the sub gear-shifting drive gears and asecond sub gear-shifting drive gear of the sub gear-shifting drivegears, the sub gear-shifting input mechanism includes a subgear-shifting input gear, the sub gear-shifting input gear is engagedwith the first sub gear-shifting drive gear, the second subgear-shifting drive gear is the one sub gear-shifting drive gear, thesub gear-shifting connection mechanism is coupled to the second subgear-shifting drive gear.
 10. The transmission apparatus of claim 9,wherein, the sub gear-shifting part includes a sub gear-shifting outputmechanism configured to output a driving power in which the second gearshifting is performed, the sub gear-shifting drive mechanism includes asecond sub gear-shifting sleeve, a connection shaft, a first connectiongear, and a second connection gear, the second sub gear-shifting sleeveis selectively connected to a third sub gear-shifting drive gear of thesub gear-shifting drive gear for the second gear shifting, and iscoupled to the connection shaft, the third sub gear-shifting drive gearis connected to the first sub gear-shifting drive gear, and is idlycoupled to the connection shaft, the first sub gear-shifting drive gearincludes a first input gear for being engaged with the sub gear-shiftinginput gear, and a first sub output gear for being engaged with the thirdsub gear-shifting drive gear, the connection shaft connects the secondsub gear-shifting sleeve to the first connection gear, the firstconnection gear is coupled to the connection shaft, and is engaged withthe second connection gear, and the second connection gear is coupled tothe sub gear-shifting output mechanism.
 11. The transmission apparatusof claim 10, wherein the second sub gear-shifting sleeve is positionedbetween the third sub gear-shifting drive gear and the first connectiongear.
 12. The transmission apparatus of claim 10, wherein the third subgear-shifting drive gear is positioned between the second subgear-shifting sleeve and the first connection gear.